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Introduction: Traditional methods for determining radiation dose in nuclear medicine include the Monte Carlo method, the discrete ordinate method, and the point kernel integration method. This study presents a new mathematical model for predicting the radiation dose rate in the vicinity of nuclear medicine patients., Methods: A new algorithm was created by combining the physical model of "cylinder superposition" of the human body with integral analysis to assess the radiation dose rate in the vicinity of nuclear medicine patients., Results: The model accurately predicted radiation dose rates within distances of 0.1-3.0 m, with a deviation of less than 11% compared to observed rates. The model demonstrated greater accuracy at shorter distances from the radiation source, with a deviation of only 1.55% from observed values at 0.1 m., Discussion: The model proposed in this study effectively represents the spatial and temporal distribution of the radiation field around nuclear medicine patients and demonstrates good agreement with actual measurements. This model has the potential to serve as a radiation dose rate alert system in hospital environments., Competing Interests: No conflicts of interest., (Copyright and License information: Editorial Office of CCDCW, Chinese Center for Disease Control and Prevention 2024.)

We explored the joint effects of different metabolic obesity phenotypes on all-cause and disease-specific mortality risk among the American population. Data were obtained from the National Health and Nutrition Examination Survey (NHANES) 1999-2018. Mortality outcome data were from mortality files linked to National Death Index record and follow-up information was up to December 31, 2019. 50,013 participants were finally included. Four metabolic obesity phenotypes were defined based on obesity and metabolic status: metabolically healthy obese (MHO), metabolically unhealthy obese (MUO), metabolically healthy non-obese (MHNO), and metabolically unhealthy non-obese (MUNO). Population-weighted Cox proportional hazards models were used to explore the all-cause and disease-specific mortality risk of metabolic obesity phenotypes. The all-cause mortality risk of MUO and MUNO was significantly higher than MHNO. MUNO was associated with a significantly increased risk of death from heart disease (HR: 1.40, 95% CI 1.16-1.70), hypertension (HR: 1.68, 95% CI 1.34-2.12), diabetes (HR: 2.29, 95% CI 1.67-3.15), and malignant neoplasms (HR:1.29, 95% CI 1.09-1.53). Metabolic unhealth significantly increased the risk of all-cause mortality, regardless of obesity status. Among individuals with metabolic unhealthy status, obesity significantly reduced the risk of all-cause mortality (HR: 0.91, 95% CI 0.85-0.98). Our study highlights the importance of identifying and characterizing metabolic obesity phenotypes in obese and metabolically abnormal patients, as well as healthy adults. Comprehensive evaluation of obesity and metabolic status is necessary to adopt appropriate interventions and treatment measures and maximize patient benefit., (© 2024. The Author(s).)

What Is Already Known About This Topic?: The impact of air temperature on varicella has been studied, but there is limited research exploring its effect on varicella by gender and age group., What Is Added by This Report?: We conducted a time series analysis to examine the differential effects of air temperature on varicella infection across different demographic groups. Our findings indicate that lower temperatures have a more pronounced influence on varicella incidence among males and children compared to females and adults., What Are the Implications for Public Health Practice?: These findings can assist in identifying populations that are vulnerable to temperature-related varicella and in guiding the implementation of effective measures for varicella control., Competing Interests: No conflicts of interest., (Copyright and License information: Editorial Office of CCDCW, Chinese Center for Disease Control and Prevention 2024.)

Introduction: Varicella outbreaks significantly disrupt schools and other child-centered institutions. This study aimed to identify patterns and epidemiological features of varicella outbreaks in China from 2006 to 2022., Methods: Data were extracted from outbreak reports submitted to the Public Health Emergency Reporting Management Information System within the specified timeframe. Analytical methods included Spearman correlation tests and the Mann-Kendall trend tests, conducted using R software to analyze and summarize reported data. Additionally, statistical analyses of trends and epidemiological characteristics were performed using SPSS software., Results: Between 2006 and 2022, a total of 11,990 varicella outbreaks were reported in China, resulting in 354,082 cases. The attack rates showed a decreasing trend over the years (Z=-4.49, P <0.05). These outbreaks occurred in two peaks annually. The eastern region accounted for the highest number of outbreaks (31.53%), followed by the southwestern (24.22%) and southern (17.93%) regions. Varicella outbreaks were most common in elementary schools. Most of the outbreaks (60.43%) were classified as Grade IV (general) severity, with 86.41% of the outbreaks having 10-49 cases. The median and inter-quartile ranges (IQR) of the duration of outbreaks, response time, and case counts were 21 (10, 39) days, 4 (0, 12) days, and 23 (16, 35) cases, respectively. These variables showed a positive correlation ( P <0.001)., Conclusions: Varicella outbreaks exhibited fluctuating trends, initially decreasing until 2012, followed by an increase, reaching the highest peak in 2018-2019. Continual monitoring of varicella epidemiology is necessary to assess the burden of the disease and formulate evidence-based strategies and policies for its prevention and control., Competing Interests: No conflicts of interest., (Copyright and License information: Editorial Office of CCDCW, Chinese Center for Disease Control and Prevention 2023.)

Introduction: Varicella, a prevalent respiratory infection among children, has become an escalating public health issue in China. The potential to considerably mitigate and control these outbreaks lies in surveillance-based early warning systems. This research employed an autoregressive integrated moving average (ARIMA) model with the objective of predicting future varicella outbreaks in the country., Methods: An ARIMA model was developed and fine-tuned using historical data on the monthly instances of varicella outbreaks reported in China from 2005 to 2018. To determine statistically significant models, parameter and Ljung-Box tests were employed. The coefficients of determination (R 2 ) and the normalized Bayesian Information Criterion (BIC) were compared to selecting an optimal model. This chosen model was subsequently utilized to forecast varicella outbreak cases for the year 2019., Results: Four models passed parameter (all P <0.05) and Ljung-Box tests (all P >0.05). ARIMA (1, 1, 1)×(0, 1, 1) 12 was determined to be the optimal model based on its coefficient of determination R 2 (0.271) and standardized BIC (14.970). Fitted values made by the ARIMA (1, 1, 1)×(0, 1, 1) 12 model closely followed the values observed in 2019, the average relative error between the actual value and the predicted value is 15.2%., Conclusion: The ARIMA model can be employed to predict impending trends in varicella outbreaks. This serves to offer a scientific benchmark for strategies concerning varicella prevention and control., Competing Interests: No conflicts of interest., (Copyright and License information: Editorial Office of CCDCW, Chinese Center for Disease Control and Prevention 2023.)

The selective detection of mannose is significant for tumor early diagnosis. However, current methods for detecting mannose are expensive and time-consuming, limiting their application. In this paper, we have obtained a 25-layer positively charged micellar/LDHs nanocomposite film system by electrostatic layer-by-layer assembly with reference to the unique properties of homogeneous charge ion attraction and charge overcompensation in biomolecules: hexadecyl trimethylammonium bromide (CTAB) was used to coat neutral molecules of fluorescein (FLU) to form (FLU@CTAB) cationic micelles, which were electrostatically assembled with laminate positively charged layered double hydroxides (LDHs) nanosheets to form (FLU@CTAB/LDHs) n ultrathin films (UTFs) by the layer-by-layer electrostatic assembly, where the mediating role of the Br - counteranion had a profound effect on the success of the assembly. Moreover, compared to pure FLU solution, the fluorescence intensity and the lifetime of (FLU@CTAB/LDHs) 20 UTFs were enhanced by 1.6 and 2 times, respectively. (FLU@CTAB/LDHs) 20 UTFs exhibited selective detection for d-mannose with a detection limit of 0.05 mg·mL -1 . Therefore, the (FLU@CTAB/LDHs) n UTFs can be a novel biosensor. Compared to conventional powder sensors, (FLU@CTAB/LDHs) n thin-film fluorescent sensors are more promising for device implementation. Moreover, the design strategy of positively charged micellar/LDHs nanocomposite systems breaks the current limitation that LDHs can only be assembled with anions or neutral molecules and extends the scope of counterion-mediated host-guest to the nanosheet-micellar system.

What Is Already Known About This Topic?: Herpes zoster (shingles) is a common skin condition in older adults, which usually presents as a painful rash with blisters. Vaccination is the most effective method to prevent shingles. However, there is not sufficient population-based epidemiological data in China to optimize the timing of zoster vaccination., What Is Added by This Report?: Clustering analyses of population-wide epidemiological data from the Healthcare Big Data Platform in Yichang, China showed that the average annual zoster incidence is the highest among people 55 years or older, at 10 cases per thousand persons per year, making this age group the optimal target population for vaccination. Incidence was lower but increased with age among younger adults, 28-54 years old., What Are the Implications for Public Health Practice?: With limited vaccination resources, zoster vaccinations should be targeted at adults 55 years or older who are at the greatest risk for shingles. Research should be conducted to understand the risk of shingles among young and middle-aged adults and identify triggers of shingles: potentially leading to preventive measures., Competing Interests: No conflicts of interest., (Copyright and License information: Editorial Office of CCDCW, Chinese Center for Disease Control and Prevention 2022.)

The resource exhaustion and environmental assessment driven by sustainable development make recycle of spent LIBs urgent to be achieved. However, the conventional recycling processes are quite complicated in terms of the tedious steps and secondary contamination. In this paper, hydrosoluble naphthalenedisulfonic acid is firstly proposed to selectively extract valuable metals (Co and Li) for the regeneration of battery materials. Lithium is selectively recovered as lithium enriched solution with a high yield of 99%, while 96.6% cobalt remains in a complex-precipitate benefited from the high acidity and coordination role of naphthalenedisulfonic acid. The leaching of Li fits well with the logarithmic rate law model with an activation energy of 32.42 kJ/mol. Additionally, the regenerated lithium-ion battery active materials (Co 3 O 4 anode and LiCoO 2 cathode) prepared from the cobalt complex-precipitate and lithium-enriched solution exhibit excellent discharged-charged performances and rate capability. This feasible strategy assisted by multifunctional naphthalenedisulfonic acid may offer an alternative option for the simultaneous recovery of Li and Co and the rational resource utilization of spent lithium-ion batteries., (Copyright © 2021. Published by Elsevier Ltd.)

Inefficient flotation of bastnaesite remains a challenge in the production of rare earth elements. This study aimed to investigate the dissolution and adsorption behaviour of species that are commonly released into bastnaesite flotation pulp from Ca/Ba-bearing gangue minerals. The influence and corresponding mechanisms on the bastnaesite mineral surface and collectors, namely sodium oleate (NaOL), were evaluated experimentally based on micro-flotation, zeta potentials, in situ attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), and X-Ray photoelectron spectroscopy (XPS) analyses. The flotation recovery of bastnaesite significantly decreased from ∼95% to ∼25%, ∼15%, ∼80%, ∼25% when exposed to calcite, fluorite, barite, and mixed dissolved species, respectively. The zeta potential of bastnaesite was pH sensitive, indicating that H + and OH - determine the surface potential of bastnaesite. Solution chemistry analyses revealed that the presence of the dissolved species differed at various pH values. In situ ATR-FTIR demonstrated the different effects of the dissolved species from calcite, fluorite, and barite on collector adsorption. The former two dissolved species mainly depressed the chemisorption of the NaOL monomers (RCOO ‒ ), whereas calcite also affected the physical adsorption of the oleic acid molecular dimer (RCOOH·RCOO ‒ ). Moreover, the barite dissolved species only affected the physical adsorption of the NaOL species. The results of XPS analysis revealed that dissolved species from these three gangues could pre-adsorbed onto bastnaesite and affected the interaction with the collector. Density functional theory calculations were employed to provide further theoretical insights into the interactions between the dissolved species from calcite, fluorite, and barite and NaOL., Competing Interests: The authors declare that they have no conflicts of interest in this work., (© 2021 The Authors. Publishing Services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd.)

The explosively growing demand for electrical energy is generating a great deal of spent lithium-ion batteries (LIBs). Therefore, a simple and effective strategy for the sustainable recycling of used batteries is urgently needed to minimize chemical consumption and to reduce the associated environmental pollution. In this work, 2-naphthalenesulfonic acid is innovatively proposed for the highly-selective recovery of valuable metals. Impressively, lithium and cobalt are simultaneously separated through a single-step process, in which 99.3% of lithium is leached out as Li + enriched solutions while 99% of cobalt is precipitated as cobalt-naphthalenesulfonate. The obtained lithium enriched solutions are recovered as Li 2 CO 3 . The cobalt-naphthalenesulfonate with high purity (99%) is ready to be transformed into Co 3 O 4 , and then generated into LiCoO 2 by reacting with the above-obtained Li 2 CO 3 . The cathode material LiCoO 2 with micro/nanostructures exhibits excellent electrochemical properties. Characterization results confirm the coordination structure of the extracted cobalt complex (Co(NS)2•6H 2 O). Finally, compared to other selective metal extraction techniques, this strategy avoids additional separation and purification processes, thus improving the recycling efficiency. Overall, this route can be extended to selectively extract valuable metals from other types of cathode materials in spent LIBs as a sustainable approach., (Copyright © 2021. Published by Elsevier B.V.)

The strategy of enhancing the surface activity by preadsorption of metal ions (surface activation) is an effective way to promote the adsorption of surfactant on surfaces, which is very important in surface process engineering. However, the adsorption mechanism of surfactant (collector) on the surface preadsorbed by metal ions in the explicit solution phase is still poorly understood. Herein, the effects of hydration on the adsorption of benzohydroxamic acid (BHA) onto the oxide mineral surface before and after lead-ion activation are investigated by first-principles calculations, owing to its importance in the field of flotation. The results show that the direct adsorption of BHA on the hydrated surface is not thermodynamically allowed in the absence of metal ions. However, the adsorption of BHA onto the lead-ion-activated surface possesses a very low barrier and a very negative reaction energy difference, indicating that the adsorption of BHA on hydrated Pb 2+ at cassiterite surface is very favorable in both thermodynamics and kinetics. In addition, the adsorption of BHA results in the dehydration of hydrated Pb 2+ . More interestingly, the surface hydroxyl groups could participate in and may promote the coordination adsorption through proton transfer. This work sheds some new lights on understanding the roles of interfacial water and the mechanisms of metal-ion surface activation.

Bauxite residue is a kind of strong alkaline waste produced in the production of alumina. Its long-term storage poses a potential threat to the environment. With the tightening of environment policies in various countries, the strong alkalinity of bauxite residue has become a bottleneck restricting the sustainable development of aluminum industry all over the world. This review covers the composition characteristics of bauxite residue, and describes the Bayer process in detail, where emphasis is put on the formation of alkaline substances in bauxite residue and its release process in long-term storage. This review focuses on several typical processes for the management of bauxite residue alkalinity in recent decades around the world. The phase transformation mechanisms, merits and limitations, as well as application status are discussed. The potential application values of these typical methods are evaluated based on process characteristics. The large amount and varied characteristics of bauxite residue determine that it is unrealistic to solve the dealkalization problem of all bauxite residue with one method. It is recommended that the appropriate dealkalization process of bauxite residue should be selected according to the characteristics of bauxite residue and regional resources, as well as the planning of subsequent application., (Copyright © 2020 Elsevier B.V. All rights reserved.)

What Is Already Known on This Topic?: The incidence of diabetes is on the rise in the world, and it is increasingly affecting young people. The American Diabetes Association (ADA) has published the 2020 Diabetes Medical Standard, but there is no blood glucose standard for teenagers by age and sex., What Is Added by This Report?: In this study, quantile regression was used to analyze the data of National Health and Nutrition Examination Survey (NHANES) and found that blood glucose varied significantly based on demographics., What Are the Implications for Public Health Practice?: This study provides reference for formulating the normal ranges of adolescent blood glucose and helping to screen out high-risk groups at an early stage for key interventions. The quantile regression method can give a set of curves, which could better describe the situation., (Copyright and License information: Editorial Office of CCDCW, Chinese Center for Disease Control and Prevention 2021.)

What is already known about this topic?, The World Health Organization's (WHO) Global Health Estimates (GHE) reported that acute hepatitis caused 9,213 deaths and 307,720 person years of disability-adjusted life years (DALYs) in 2016, and acute hepatitis B accounted for 85.81% of all DALYs among acute hepatitis types A, B, C, and E in China., What is added by this report?, In China, the percent changes in years lived with disability (YLDs) due to acute hepatitis A, B, and E in groups aged 50-69 years and 70 years or more and in all age groups for acute hepatitis C were increased from 2000 to 2019., What are the implications for public health practices?, Effective vaccines, interventions, and treatments are key approaches to achieve the WHO's goal of reducing new hepatitis infections by 90% and deaths by 65% between 2016 and 2030., Competing Interests: Conflict of interest: No conflicts of interest were reported., (Copyright and License information: Editorial Office of CCDCW, Chinese Center for Disease Control and Prevention 2020.)

Lead(II)-benzohydroxamic acid (Pb-BHA) complex collectors perform well with respect to scheelite flotation, and, due to their structure, they are widely used for industrial purposes. This paper examines the controversial issue of whether "O, O" five-membered ring or "N, O" four-membered ring complexes are formed when BHA coordinates with Pb ions, with their structure being comprehensively studied from the aspect of colloid and interface science. The configurations of Pb-BHA complexes are examined in a solution and on a mineral surface with experimental and computational methods. Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and density functional theory (DFT) revealed that the five-membered ring is the dominant form of Pb-BHA complexes in a solution, whereas four-membered ring complexes are the stronger electron acceptor of the two. Moreover, XPS and time-of-flight secondary ion mass spectrometry (TOF-SIMS) confirmed that the four-membered ring complexes are stable with respect to being adsorbed on the scheelite surface. Therefore, although the four-membered ring is not as stable as the five-membered ring in a solution, it offers advantages with respect to adsorption on an electron-rich mineral surface during short-flotation processes., (Copyright © 2019. Published by Elsevier Inc.)

The comprehensive recovery of iron and titanium resources from early tailings were systematically attempted from fundamental work to industrial application. Geochemical characterization of the tailings was first conducted, followed by the iron recovery and titanium recovery. Iron recovery was mainly achieved through a series of magnetic separation, and titanium recovery was on the combination of magnetic pre-concentration and flotation separation. Special for titanium recovery, different pretreatment methods including ultrasonic cleaning and attrition-scrubbing were studied to reduce the influence of serious surface pollution of early tailings on ilmenite floatability, and attrition-scrubbing proved to be the best one. Associated mechanisms of flocculants influence on ilmenite floatability and the attrition-scrubbing effects were explored using micro-flotation and XPS tests. After a series of fundamental studies, the industrial production of iron and ilmenite concentrate went into operation and the industrial debugging results were roughly satisfactory. At last, a brief economic analysis was given for the present work., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Pyrrhotite is a potential source of S 2 - for the sulfide precipitation of nonferrous metal ions in hydrometallurgy and waste water treatment. In this study, different pyrrhotite crystals were prepared using zero-valent iron and sulfur to determine the effects of the pyrrhotite's structure on the sulfide precipitation of copper ions. The results indicate that the sulfide precipitation of copper ions highly depends on the crystal structure and crystallinity of pyrrhotite. Monoclinic pyrrhotite was found to be the most effective for copper sulfide precipitation, which can be used for the selective precipitation of copper ions from arsenic wastewater. More than 96% copper ions were removed with little loss of arsenic, contributing to a copper product of 20.2% Cu and 0.7% As, which can serve as raw materials of copper metallurgy. X-ray diffraction analysis showed the presence of CuS and (Cu x Fe 1 - x )S, indicating that most copper ions precipitated as CuS and some copper ions entered the FeS lattice by a lattice substitution reaction. Therefore, monoclinic pyrrhotite may provide an alternative solution for the selective precipitation of copper from arsenic wastewater., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Discovering cathode materials composed of earth-abundant elements has become the current priority for developing sodium-ion batteries (SIBs) to meet the ever-increasing demand of large-scale energy storage. Herein, for the first time, layered Na x MO 2 (M = Cu, Fe, Mn) cathodes are successfully prepared by directly using concentrated chalcopyrite ores as precursors. Greatly, impurity elements like Si and Ca are found to be crucial to tailoring the phase structure of as-obtained layered oxides as a P2 or O3 type, which removes the traditional concern that the impurities may restrict the utilization of natural ores. More interestingly, a certain amount of the Ca elements remaining in the Na sites through a self-doping process endows the P2-type products with enhanced structural stability. In half-cells, P2-type Na x MO 2 with self-doped Ca elements shows superior rate capability and cycling stability (56 mAh g -1 at 5 C and 90% capacity retention after 100 cycles at 1 C). In contrast, less impurity elements are favorable for O3-type oxides to achieve a high capacity of 107 mAh g -1 at 0.1 C and 84% capacity retention after 200 cycles at 2 C. This new strategy would efficiently shorten the process for preparing electrode materials and open a feasible route to construct cheap and durable SIBs.

Traditional chemical precipitation of phosphates from wastewater is somewhat inefficient because it produces some ultrafine hydroxyapatite particles that are difficult to settle. In this study, magnetic seeds with a core-shell structure were prepared by sulfation roasting for magnetic flocculation of those fine particles. Zeta potential measurements show that the hydroxyapatite particles are positively charged at pH 10, whereas the magnetic seeds are negatively charged. The Derjaguin-Landau-Verwey-Overbeek calculation indicates that the van der Waals force between the magnetic seeds and hydroxyapatite particles is always attractive. Moreover, the electrostatic attraction also contributes to aggregation of the magnetic seeds and hydroxyapatite particles. Orthogonal experiments show that the main factor affecting the magnetic flocculation is the dosage of magnetic seeds, and polymeric ferric sulfate also plays an important role. Under the optimal magnetic flocculation experimental conditions, the turbidity of wastewater after magnetic separation was only 16.388 NTU, contributing to the removal of phosphate contaminants. Therefore, magnetic flocculation and magnetic separation may provide an alternative solution for efficient purification of phosphate-containing wastewater., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Previous studies have shown that Pb-BHA complexes (lead complexes of benzohydroxamic acid) have better collecting ability and can be used in flotation experiments with BHA acting as a collector and lead ions acting as activators. However, the structures of Pb-BHA complexes adsorbed on a mineral surface remain unclear. In this work, the adsorption behavior of Pb-BHA complexes on the scheelite surface was studied by flotation experiments and adsorption capacity measurements, and the structures of the adsorbed Pb-BHA complexes were determined using X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (TOF-SIMS). The adsorption capacity results showed that more BHA was adsorbed on the scheelite surface in Pb-BHA flotation, and the XPS and TOF-SIMS analysis showed that the species of Pb-BHA complexes adsorbed on the scheelite surface were similar in activation flotation and Pb-BHA flotation. Therefore, the different contents of the complexes on the scheelite surface were responsible for the flotation behavior. XPS and TOF-SIMS showed that BHA combined with lead ions to form complexes with different structures, such as five- and four-membered ring structures. Structure fragment inference based on the measurements indicated that lead ions formed monomer complexes with two BHAs, and that lead hydroxide polymers with a certain degree of polymerization bonded with oxygen atoms in the complexes. The Pb-BHA complexes combine with oxygen atoms on the scheelite surface to form an adsorbate, rendering the surface hydrophobic., (Copyright © 2019 Wei, Sun, Hu, Han, Sun, Wang, Zhu, Li and Song.)

Core-shell magnetic seeds with certain adsorption capacity that were prepared by sulfated roasting, served as the core of a magnetic separation technology for purification of starch wastewater. XRD and SEM results indicate that magnetite's surface transformed to be porous α-Fe 2 O 3 structure. Compared with magnetite particles, the specific surface area was significantly improved to be 8.361 from 2.591 m 2 /g, with little decrease in specific susceptibility. Zeta potential, FT-IR and XPS experiments indicate that both phosphate and starch adsorbed on the surface of the core-shell magnetic seeds by chemical adsorption, which fits well with the Langmuir adsorption model. The porous surface structure of magnetic seeds significantly contributes to the adsorption of phosphate and starch species, which can be efficiently removed to be 1.51 mg/L (phosphate) and 9.51 mg/L (starch) using magnetic separation., (Copyright © 2019. Published by Elsevier B.V.)

Even though black phosphorus (BP) has exhibited outstanding capabilities in biomedical, physical, and energy fields, the issues of degradation under ambient conditions and unreactive functional interface limit its further application. There are numerous methodologies utilized to prevent BP degradation; however, these methods usually generate further problems and normally do not involve alterations to the chemically inert BP. Herein, for the first time, we propose a simple and efficient strategy to prepare and modify BP nanosheets (p-BPNSs) by employing aromatic 1-pyrenylbutyric acid through a noncovalent π-π stacking interaction. This strategy not only adopts a novel strategy for enhancing the stability of BPNSs but also paves a convenient way to anchor other active biomolecules such as a targeting effect to extend the biomedical applications of BPNSs. The modified p-BPNSs exhibit enhanced physical and chemical stabilities as well as rich carboxyl groups for further modification. In this work, RGD-modified p-BPNSs exhibit targeted photothermal therapy ability against cancer in both in vitro and in vivo studies, owing to anchoring of arginine-glycine-aspartic acid (RGD) tripeptides, which could target nanosheets into the tumor site through systematic circulation. Consequently, this work not only provides a new concept for modifying and protecting the BP but also opens a novel window for extending the biomedical application of BP by surface engineering.

Recycling lithium and graphite from spent lithium-ion battery plays a significant role in mitigation of lithium resources shortage, comprehensive utilization of spent anode graphite and environmental protection. In this study, spent graphite was firstly collected by a two-stage calcination. Secondly, under the optimal conditions of 1.5 M HCI, 60 min and solid-liquid ratio (S/L) of 100 g·L -1 , the collected graphite suffers simple acid leaching to make almost 100% lithium, copper and aluminum in it into leach liquor. Thirdly, 99.9% aluminum and 99.9% copper were removed from leach liquor by adjusting pH first to 7 and then to 9, and thenthe lithium was recovered by adding sodium carbonate in leach liquor to form lithium carbonate with high purity (>99%). The regenerated graphite is found to have high initial specific capacity at the rate of 37.2 mA·g -1 (591 mAh·g -1 ), 74.4 mA·g -1 (510 mAh·g -1 ) and 186 mA·g -1 (335 mAh·g -1 ), and with the high retention ratio of 97.9% after 100 cycles, it also displays excellent cycle performance at high rate of 372 mA·g -1 . By this process, copper and lithium can be recovered and graphite can be regenerated, serving as a sustainable approach for the comprehensive utilization of anode material from spent lithium-ion battery., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

This study introduces the use of a waste by-product from wet limestone flue gas desulfurization as a potential material for fluoride removal. Systematic laboratory-scale experiments were tested to identify the fluoride removal performance and determine the underlying mechanism. Flue gas desulfurization (FGD) gypsum removes 93.31% of fluoride from 109 mg/L to 7.3 mg/L. Fluoride can be efficiently removed at the optimum pH range of 5-11. Kinetics analysis indicates that the theoretical fluoride capacity at 1 g/L FGD gypsum is 96.9 mg/g. Equilibrium speciation analysis indicates that the decrease of system pH to lower than 5 is unsuitable for the formation of calcium fluoride, and the increase of system pH to higher than 11 opposes calcium release from FGD gypsum. Thermodynamic analysis confirms the feasibility of converting calcium sulphate into calcium fluoride at pH > 5. FGD gypsum and precipitates were characterized to describe their surface morphology, elemental composition and crystalline phase. Results indicate that FGD gypsum removes fluoride through the combination of calcium with fluoride to generate calcium fluoride., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The transition-metal sulfide, CuS, is deemed a promising material for energy storage, mainly derived from its good chemisorption and conductivity, although serious capacity fading limits its advancement within reversible lithium storage. Learning from the gold extraction method utilizing the lime-sulfur-synthetic-solution, a CuS@S hybrid utilizing CaS x as both sulfur resource and reductant-oxidant is prepared, which is an efficient approach to apply the metallurgy for the preparation of electrode materials. Regulating the amount of CuCl 2 , the CuS@S is induced to reach a molecular-level hybrid. When utilized as an anode within a lithium-ion battery, it presents the specific capacity of 514.4 mA h g -1 at 0.1 A g -1 over 200 cycles. Supported by the analyses of pseudo-capacitive behaviors, it is confirmed that the CuS matrix with the suitable content of auxiliary sulfur could improve the durability of the CuS-based anode. Expanding the wider application within lithium-sulfur batteries, the synchronous growth of CuS@S exhibits stronger chemisorption with polysulfides than the mechanical mixture of CuS and S. A suite of in situ electrochemical impedance spectroscopy studies further investigates the stable resistances of the CuS@S within the charge/discharge process, corresponding to the reversible structure evolution. This systematic work may provide a practical fabricating route of metal sulfides for scalable energy storage applications.

Precipitation of goethite on magnetic nanoparticles (MNPs) has been proposed as an effective means to separate goethite from calcium sulfate in the iron removal process of zinc hydrometallurgy, which allows reuse of the hazardous residues. This study focuses on investigating the underlying mechanisms of goethite precipitation on magnetite and maghemite MNPs, providing insights on Fe(III) aq adsorption and nucleation of goethite on MNPs. A predictive surface complexation/precipitation model of the system was developed based on the results from two different types of experiments: the potentiometric titration of MNPs to calculate proton binding constants ( K a ) of discrete MNP surface functional groups and the corresponding site concentrations; and adsorption of Fe(III) aq onto MNP surfaces to determine metal binding constants ( K f ). The composition of the surface complexes on MNPs was determined by time-of-flight secondary ion mass spectrometry. The results indicated the formation of polynuclear surface complexes. The content of polynuclear surface complexes was found to be significantly higher on maghemite MNPs than on magnetite MNPs. This trend is consistent with our experimental results of a greater goethite precipitation on maghemite than on magnetite. Overall, the formation of Fe(III) polynuclear surface complexes correlates directly to the nucleation and precipitation of goethite on the surfaces of both types of MNPs.

Development of mineral resources and the increasing mining waste emissions have created a series of environmental and health-related issues. Nowadays, the ecological restoration of mining tailings has become one of the urgent tasks for mine workers and environmental engineers all over the world. Aim of the present paper is to highlight the previous restoration techniques and the challenges encountered during the restoration of mine tailings. As it is a common practice that, before restoring of tailings, the site should be evaluated carefully. Studies showed that the mine tailings' adverse properties, including excessive heavy metal concentration, acidification, improper pH value, salinization and alkalization, poor physical structure and inadequate nutrition, etc., are the major challenges of their restoration. Generally, four restoration technologies, including physical, chemical, phytoremediation, and bioremediation, are used to restore the mining tailings. The working mechanism, advantages, and disadvantages of these techniques are described in detail. In addition, selection of the suitable restoration techniques can largely be carried out by considering both the economic factors and time required. Furthermore, the ecosystem restoration is perceived to be a more promising technology for mine tailings. Therefore, this extensive review can act as a valuable reference for the researchers involved in mine tailing restoration.

Huge amount of flue gas desulphurization (FGD) gypsum not only occupies the farmland but also causes severe pollution to the surrounding environment. The most effective way to achieve a high-value utilization of FGD gypsum is to prepare short columnar α-calcium sulfate hemihydrate (α-HH) since short columnar crystals show better mechanical strength than needle-like ones. Here, malic acid, a prolific, inexpensive and environment-friendly modifier was explored for the first time to effectively tune the crystal morphology of α-HH prepared from FGD gypsum in glycerol-water-NaCl solutions. When the concentration of malic acid reached 18.54 × 10 -4  mol/kg, α-HH crystals with an average aspect (length-to-diameter) ratio of 1.9 (compared to 29.4 in the absence of malic acid) were prepared. The selective complexation of malic acid with Ca active sites on different α-HH crystal planes played a dominant role in the α-HH crystal morphology transformation, which was then explained by the surface broken bonds theory for the first time. The broken bond number per active Ca atom (N b per Ca ) and broken bond density of Ca atoms (D b Ca ) on the (2 0 4) end plane were larger than those on the (0 2 0) or (2 0 0) side planes. Therefore, the (2 0 4) end plane was more reactive with organics, resulting in the preferential adsorption of malic acid on the end planes, which reduced the specific surface energy of (2 0 4) and led to an increased exposure of this plane and a decreased exposure of (0 2 0) or (2 0 0) side planes in the final α-HH crystals. Consequently, using malic acid as modifier, the α-HH crystal gradually transformed from a needle-like shape to a short columnar one. This work provided important insights into and perspectives for the selection of crystal modifiers and explanation of the mechanism during the preparation of calcium-containing crystals with controllable morphology., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Metal ions are commonly used as activators to improve the anionic collector flotation of oxide minerals with an accepted activation mechanism that the prior addition of metal ions can adsorb onto the oxide mineral surface to increase the number of active sites for subsequent attachment of a collector. The improved flotation of cassiterite (or scheelite) with the use of lead nitrate (LN) as the activator and benzohydroxamic acid (BHA) as the collector is a typical example. However, our recent research showed that a soluble metal-organic complex (lead-BHA complex) produced by pre-mixing LN and BHA further improved the collecting ability and selectivity in the flotation of cassiterite and for that, the existing activation mechanism cannot completely explain this further improved performance. We believe that the lead ion and its hydroxide species can directly interact with water molecules to form Pb(H 2 O) n 2+ and Pb(OH)(H 2 O) n + complexes in water solution, and those bonded water molecules will in turn affect the interaction of (hydroxide) lead ion with the cassiterite surface and the BHA. In this work, solution chemistry calculation was used to identify the major active components of the lead-BHA complex in water solution at different pH levels, and based on density functional theory, the adsorption energies of different activation mechanisms were calculated via accurate first-principle calculations, indicating a much stronger interaction of the adsorption of HO-Pb-BHA complex on cassiterite surface (-48.11 kcal/mol) compared with that of the sequential adsorption of Pb(OH)(H 2 O) 5 + and BHA anion (-13.29 kcal/mol) at optimal flotation pH 8-9. That is, the difference in two activation systems can be explained based on thermodynamics. With such, a new hypothetic activation model was proposed to explain the improved performance of soluble lead-BHA complex and then, the proposed model was verified by the flotation experiment and adsorption test results. This work can help enrich the activation theory of metal ions in anionic collector flotation of minerals., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Amphiphilic biomembrane structures determine significant biological functions and are extensively used as structure models to learn from and study nature. Many biomimetic amphiphilic membranes have been established to connect natural and artificial substances. In this paper, taking advantage of the intercalation and assembly properties of the layered double hydroxides (LDHs), the amphiphilic LDHs/arachidic acid (AA) nanocomposite Langmuir-Blodgett (LB) ultrathin films (UTFs) were fabricated by the LB technology. The CdTe quantum dots (QDs) were incorporated into the LB monolayers via a layer-by-layer (LbL) method based on the electrostatic interaction between LDHs and CdTe QDs. The amphiphilic (CdTe QDs@LDHs/AA) n nanocomposite LB UTFs were composed of CdTe QDs@LDHs hydrophilic segments and hydrophobic layers formed by the long alkyl chain of AA. Because of the spacing effect of amphiphilic AA, the fluorescence intensity of CdTe QDs was enhanced about 10-fold, and the fluorescence lifetimes (38.96 ns vs 17.63 ns) and quantum yield (QY %) (17.56 vs 5.96) have been improved compared to that of the counterpart by the LbL method. The fluorescence intensity of CdTe QDs increased by about fivefolds in the presence of LDHs compared with the counterpart without LDHs, which can be attributed to the two-dimensional confinement effect of LDHs. The amphiphilic nanocomposite LB UTFs were used to detect volatile organic compounds (VOCs) with various polarities. The amphiphilic nanocomposite LB UTFs exhibited two kinds of fluorescence response to VOCs: irreversible fluorescence quenching for amine VOCs with strong polarity and reversible fluorescence enhancement for non-amine VOCs. The fluorescence response mechanism was investigated and can be attributed to the amphiphilic structure of the LB UTFs and the selective adsorption of different VOC molecules. Therefore, this fluorescence quenching/enhancement dual-model response of amphiphilic nanocomposite LB UTFs can be applied into the selective detection of VOCs.

Restricted by the dissatisfied capacity of traditional materials, lithium-ion batteries (LIBs) still suffer from the low energy-density. The pursuing of natural electrode resources with high lithium-storage capability has triggered a plenty of activities. Through the hydro-refining process of raw molybdenite ore, containing crushing-grinding, flotation, exfoliation, and gradient centrifugation, 2D molybdenum disulfide (MoS 2 ) with high purity is massively obtained. The effective tailoring process further induce various sizes (5, 2, 1 and 90 nm) of sheets, accompanying with the increasing of active sites and defects. Utilized as LIB anodes, size-tuning could serve crucial roles on the electrochemical properties. Among them, MoS 2 -1 μm delivers an initial charge capacity of 904 mAh g -1 , reaching up to 1,337 mAh g -1 over 125 loops at 0.1 A g -1 . Even at 5.0 A g -1 , a considerable capacity of 682 mAh g -1 is remained. Detailedly analyzing kinetic origins reveals that size-controlling would bring about lowered charge transfer resistance and quicken ions diffusion. The work is anticipated to shed light on the effect of different MoS 2 sheet sizes on Li-capacity ability and provides a promising strategy for the commercial-scale production of natural mineral as high-capacity anodes.

Anisotropic surface properties of minerals play an important role in a variety of fields. With a focus on the two most intensively investigated silicate minerals (i.e., phyllosilicate minerals and pegmatite aluminosilicate minerals), this review highlights the research on their anisotropic surface properties based on their crystal structures. Four surface features comprise the anisotropic surface chemistry of minerals: broken bonds, energy, wettability, and charge. Analysis of surface broken bond and energy anisotropy helps to explain the cleavage and growth properties of mineral crystals, and understanding surface wettability and charge anisotropy is critical to the analysis of minerals' solution behavior, such as their flotation performance and rheological properties. In a specific reaction, the anisotropic surface properties of minerals are reflected in the adsorption strengths of reagents on different mineral surfaces. Combined with the knowledge of mineral crushing and grinding, a thorough understanding of the anisotropic surface chemistry properties and the anisotropic adsorption behavior of minerals will lead to the development of effective relational models comprising their crystal structure, surface chemistry properties, and targeted reagent adsorption. Overall, such a comprehensive approach is expected to firmly establish the connection between selective cleavage of mineral crystals for desired surfaces and designing novel reagents selectively adsorbed on the mineral surfaces. As tools to characterize the anisotropic surface chemistry properties of minerals, DLVO theory, atomic force microscopy (AFM), and molecular dynamics (MD) simulations are also reviewed., (Copyright © 2018 Elsevier B.V. All rights reserved.)

A novel compound 4-amino-5-mercapto-1,2,4-triazole was first synthesized, and its selective adsorption mechanism on the surface of chalcopyrite was comprehensively investigated using UV-vis spectra, zeta-potential, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy measurements (XPS), time-of-flight secondary ion mass spectrometry (ToF-SIMS), and first principles calculations. The experimental and computational results consistently demonstrated that AMT would chemisorb onto the chalcopyrite surface by the formation of a five-membered chelate ring. The first principles periodic calculations further indicated that AMT would prefer to adsorb onto Cu rather than Fe due to the more negative adsorption energy of AMT on Cu in the chalcopyrite (001) surface, which was further confirmed by the coordination reaction energies of AMT-Cu and AMT-Fe based on the simplified cluster models at a higher accuracy level (UB3LYP/Def2-TZVP). The bench-scale results indicated that the selective index improved significantly when using AMT as a chalcopyrite depressant in Cu-Mo flotation separation.

Fluorite is the most important mineral source for producing fluorine-based chemicals and materials in a wide range of engineering and technological applications. In this work, atomic force microscopy was employed, for the first time, to probe the surface interactions and adhesion energy of model oleic acid (a commonly used surface modification organics for fluorite) molecules on fluorite surfaces with different orientations in both air and aqueous solutions at different pH conditions. Fitted with the Derjaguin-Landau-Verwey-Overbeek theory, the force results during surface approaching demonstrate the anisotropy in the surface charge of different orientations, with the {111} surface exhibiting a higher magnitude of surface charge, which could be attributed to the difference in the atomic composition. The adhesion measured during surface retraction shows that model oleic acid molecules have a stronger adhesion with the {100} surface than with the {111} surface in both air and aqueous solutions. The anisotropic adhesion energy was analyzed in relation to the surface atom (especially calcium) activity, which was supported by the surface free energy results calculated based on a three-probe-liquid method. Each calcium atom on the {100} surface with four dangling bonds is more active than the calcium atom on the {111} surface with only one dangling bond, supported by a larger value of the Lewis acid component for the {100} surface. The model oleic acid molecules present in the ionic form at pH 9 exhibit a higher adhesion energy with fluorite surfaces as compared to their molecular form at pH 6, which was related to the surface activity of different forms. The adhesion energy measured in solution is much lower than that in air, indicating that the solvent exerts an important influence on the interactions of organic molecules with mineral surfaces. The results provide useful information on the fundamental understanding of surface interactions and adhesion energy of organic molecules on mineral surfaces with different orientations, and the methodology can be extended to many other crystal surfaces in various interfacial processes.

The efficient separation of scheelite from calcium-bearing minerals, especially calcite, remains a challenge in practice. In this work, a novel reagent scheme incorporating a depressant of sodium hexametaphosphate (SHMP) and a collector mixture of octyl hydroxamic acid (HXMA-8) and sodium oleate (NaOl) was employed in both single and mixed binary mineral flotation, and it proved to be highly effective for the separation. Furthermore, the role of the pH value in the separation was evaluated. Additionally, the mechanism of the selective separation was investigated systemically via zeta potential measurements, fourier transform infrared (FTIR) spectroscopy analysis, X-ray photoelectron (XPS) spectroscopy analysis and crystal chemistry calculations. It turns out that the selective chemisorption of SHMP on calcite (in the form of complexation between H 2 PO 4 - /HPO 4 2- and Ca 2+ ) over scheelite is ascribed to the stronger reactivity and higher density of Ca ions on the commonly exposed surfaces of calcite minerals. The intense adsorption of HXMA-8 on scheelite over calcite due to the match of the OO distances in WO 4 2- of scheelite and CONHOH of HXMA-8 holds the key to the successful separation. We were also interested in warranting the previous claim that NaOl is readily adsorbed on both minerals via chemisorption. Our results provided valuable insights into the application of mixed collectors and an effective depressant for flotation separation., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Selective adsorption of tannic acid (TA) on calcite surfaces and the implications of this process for the separation of fluorite ore were studied by microflotation tests, surface adsorption experiments, zeta potential measurements, UV-vis analysis, and X-ray photoelectron spectroscopy (XPS) analysis. The microflotation tests indicated that TA, when added before sodium oleate (NaOl), could selectively depress calcite from fluorite at pH 7. Surface adsorption experiments revealed that TA hinders the interaction of NaOl with calcite. The zeta potential of calcite became more negative with TA than with NaOl. However, the characteristic features of TA adsorption were not observed on fluorite, suggesting that the dominant adsorption sites are dissimilar on the fluorite and calcite surfaces in the pulp. UV-vis spectroscopy, XPS, and solution chemistry analysis were utilized to obtain a better understanding of the mechanism for selective adsorption of TA as well as the key factors determined by the Ca 2+ and Ca(OH) + components on the mineral surfaces. A possible adsorption mechanism along with an adsorption mode is proposed for the surface interaction between TA and calcite., (Copyright © 2017 Elsevier Inc. All rights reserved.)

The analysis of flotation and adsorption of mixed collectors on oxide and silicate minerals is of great importance for both industrial applications and theoretical research. Over the past years, significant progress has been achieved in understanding the adsorption of single collectors in micelles as well as at interfaces. By contrast, the self-assembly of mixed collectors at liquid/air and solid/liquid interfaces remains a developing area as a result of the complexity of the mixed systems involved and the limited availability of suitable analytical techniques. In this work, we systematically review the processes involved in the adsorption of mixed collectors onto micelles and at interface by examining four specific points, namely, theoretical background, factors that affect adsorption, analytical techniques, and self-assembly of mixed surfactants at the mineral/liquid interface. In the first part, the theoretical background of collector mixtures is introduced, together with several core solution theories, which are classified according to their application in the analysis of physicochemical properties of mixed collector systems. In the second part, we discuss the factors that can influence adsorption, including factors related to the structure of collectors and environmental conditions. We summarize their influence on the adsorption of mixed systems, with the objective to provide guidance on the progress achieved in this field to date. Advances in measurement techniques can greatly promote our understanding of adsorption processes. In the third part, therefore, modern techniques such as optical reflectometry, neutron scattering, neutron reflectometry, thermogravimetric analysis, fluorescence spectroscopy, ultrafiltration, atomic force microscopy, analytical ultracentrifugation, X-ray photoelectron spectroscopy, Vibrational Sum Frequency Generation Spectroscopy and molecular dynamics simulations are introduced in virtue of their application. Finally, focusing on oxide and silicate minerals, we review and summarize the flotation and adsorption of three most widely used mixed surfactant systems (anionic-cationic, anionic-nonionic, and cationic-nonionic) at the liquid/mineral interface in order to fully understand the self-assembly progress. In the end, the paper gives a brief future outlook of the possible development in the mixed surfactants., (Copyright © 2017 Elsevier B.V. All rights reserved.)

This study investigates an environmentally friendly technology that utilizes waste by-products (waste acid and waste alkali liquids) to treat mineral processing wastewater. Chemical precipitation is used to remove silicate from scheelite (CaWO 4 ) cleaning flotation wastewater and the waste by-products are used as a substitute for calcium chloride (CaCl 2 ). A series of laboratory experiments is conducted to explain the removal of silicate and the characterization and formation mechanism of calcium silicate. The results show that silicate removal reaches 90% when the Ca:Si molar ratio exceeds 1.0. The X-ray diffraction (XRD) results confirm the characterization and formation of calcium silicate. The pH is the key factor for silicate removal, and the formation of polysilicic acid with a reduction of pH can effectively improve the silicate removal and reduce the usage of calcium. The economic analysis shows that the treatment costs with waste acid (0.63 $/m 3 ) and waste alkali (1.54 $/m 3 ) are lower than that of calcium chloride (2.38 $/m 3 ). The efficient removal of silicate is confirmed by industrial testing at a plant. The results show that silicate removal reaches 85% in the recycled water from tailings dam., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The anisotropic adsorption of sodium oleate (NaOL) on feldspar surfaces was investigated to elucidate the different flotation properties of feldspar particles of four different size ranges. Microflotation experiments showed that the feldspar flotation recovery of particles with sizes spanning different ranges decreased in the order 0-19>19-38>45-75>38-45μm. Zeta potential and FTIR measurements showed that NaOL was chemically adsorbed on the Al sites of the feldspar surface. The anisotropic surface energies and broken bond densities estimated by density functional theory calculations showed that, although feldspar mostly exposed (010) and (001) surfaces, only the (001) surfaces contained the Al sites needed for NaOL adsorption. The interaction energies calculated by molecular dynamics simulations confirmed the more favorable NaOL adsorption on (001) than (010) surfaces, which may represent the main cause for the anisotropic NaOL adsorption on feldspar particles of different sizes. SEM measurements showed that the main exposed surfaces on coarse and fine feldspar particles were the side (010) and basal (001) ones, respectively. A higher fraction of Al-rich (001) surfaces is exposed on fine feldspar particles, resulting in better floatability compared with coarse particles. XPS and adsorption measurements confirmed that the Al content on the feldspar surface varied with the particle size, explaining the different NaOL flotation of feldspar particles of different sizes. Therefore, the present results suggest that coarsely ground ore should be used for the separation of feldspar gangue minerals. Further improvements in the flotation separation of feldspar from associated valuable minerals can be achieved through selective comminution or grinding processes favoring the exposure of (010) surfaces., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Mine tailings are detrimental to natural plant growth due to their physicochemical characteristics, such as high pH, high salinity, low water retention capacity, high heavy metal concentrations, and deficiencies in soil organic matter and fertility. Thus, the remediation of mine tailings has become a key issue in environmental science and engineering. Phytoremediation, an in situ cost-effective technology, is emerging as the most promising remediation method for mine tailings by introducing tolerant plant species. It is particularly effective in dealing with large-area mine tailings with shallow contamination of organic, nutrient and metal pollutants. In this review, the background, concepts and applications of phytoremediation are comprehensively discussed. Furthermore, proper amendments used to improve the physical, chemical and biological properties of mine tailings are systematically reviewed and compared. Emphasis is placed on the types and characteristics of tolerant plants and their role in phytoremediation. Moreover, the role of microorganisms and their mechanism in phytoremediation are also discussed in-depth., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

A facile method to transform flue gas desulfurization gypsum (FGD gypsum) to α- calcium sulfate hemihydrate (α-HH) whiskers with high aspect ratios mediated by cetyltrimethylammonium bromide (CTAB) and KCl in glycerol-water solutions was studied. Addition of KCl facilitated the dissolution of calcium sulfate dihydrate (DH) and created a much higher supersaturation, which could come into being a larger driving force for the phase transformation from DH to α-HH. CTAB as the crystal modifier can significantly promoted 1-D growth of α-HH whiskers along the c axis and the presence of 0.25% CTAB (by weight of FGD gypsum) resulted in the increase of the average aspect ratio of α-HH whiskers from 28.9 to 188.4, which might be attributed to the preferential adsorption of C 16 H 33 (CH 3 ) 3 N + on the negative side facets of α-HH crystal.

Background: The United Nation's Sustainable Development Goals for 2030 include reducing premature mortality from non-communicable diseases (NCDs) by one third. To assess the feasibility of this goal in China, we projected premature mortality in 2030 of NCDs under different risk factor reduction scenarios., Methods: We used China results from the Global Burden of Disease Study 2013 as empirical data for projections. Deaths between 1990 and 2013 for cardiovascular disease (CVD), diabetes, chronic respiratory disease, cancer, and other NCDs were extracted, along with population numbers. We disaggregated deaths into parts attributable and unattributable to high systolic blood pressure (SBP), smoking, high body mass index (BMI), high total cholesterol, physical inactivity, and high fasting glucose. Risk factor exposure and deaths by NCD category were projected to 2030. Eight simulated scenarios were also constructed to explore how premature mortality will be affected if the World Health Organization's targets for risk factors reduction are achieved by 2030., Results: If current trends for each risk factor continued to 2030, the total premature deaths from NCDs would increase from 3.11 million to 3.52 million, but the premature mortality rate would decrease by 13.1%. In the combined scenario in which all risk factor reduction targets are achieved, nearly one million deaths among persons 30 to 70 years old due to NCDs would be avoided, and the one-third reduction goal would be achieved for all NCDs combined. More specifically, the goal would be achieved for CVD and chronic respiratory diseases, but not for cancer and diabetes. Reduction in the prevalence of high SBP, smoking, and high BMI played an important role in achieving the goals., Conclusions: Reaching the goal of a one-third reduction in premature mortality from NCDs is possible by 2030 if certain targets for risk factor intervention are reached, but more efforts are required to achieve risk factor reduction.

Coexistence of the polymorphic hybrid-1 and hybrid-2 conformers for a given human telomeric G-quadruplex-forming sequence (htG4) complicates its fine structure identification and limits its application as a sensor element. With help from abasic site (AP site)-engineered htG4s serving as the monomorphic representatives of the two typical hybrid conformers, we found that thioflavin T (ThT) can selectively target the hybrid-2 conformer over the hybrid-1 counterpart in monomer and tandem htG4 molecules. The htG4 that solely adopts the monomorphic hybrid-2 conformer engineered by the AP site is most efficient in lighting up ThT fluorescence in K + and a selective K + sensor is realized with a remarkable hypersaline-tolerant capability that can work even in 30000-fold excess of Na + . At 600 mM Na + , the dynamic range for K + detection can be extended to 30 mM with the limit of detection of 20 μM. This is the first report on the fluorescence discrimination of these two hybrid conformers of htG4 although they have long been categorized with their characteristically structural topologies. Our work will attract much interest in the development of sensors based on the monomorphic htG4 conformer since such high performance in sensor development has not been previously achieved., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The rapid identification of biomacromolecule structure that has a specific association with chiral enantiomers especially from natural sources will be helpful in developing enantioselective sensor and in speeding up drug exploitation. Herein, owing to its existence also in living cells, apurinic/apyrimidinic site (AP site) was first engineered into ds-DNA duplex to explore its competence in enantiomer selectivity. An AP site-specific fluorophore was utilized as an enantioselective discrimination probe to develop a straightforward chiral sensor using natural tetrahydropalmatine (L- and D-THP) as enantiomer representatives. We found that only L-THP can efficiently replace the prebound fluorophore to cause a significant fluorescence increase due to its specific binding with the AP site (two orders magnitude higher in affinity than binding with D-THP). The AP site binding specificity of L-THP over D-THP was assessed via intrinsic fluorescence, isothermal titration calorimetry, and DNA stability. The enantioselective performance can be easily tuned by the sequences near the AP site and the number of AP sites. A single AP site provides a perfect binding pocket to differentiate the chiral atom-induced structure discrepancy. We expect that our work will inspire interest in engineering local structures into a ds-DNA duplex for developing novel enantioselective sensors.

Protein immobilization is of significant interest for applications in biosensing, drug delivery and bioconversion, and challenges still remain for the in vitro immobilization and application of proteins. Due to it being non-specific to species, easy to express in cells and able to exhibit fluorescence after expression without the need for cofactors or chaperones, green fluorescent protein (GFP), together with its differently colored mutants, has been widely studied and applied. This article reports the fabrication of enhanced green fluorescent protein (EGFP)/layered double hydroxide nanosheet (EGFP/LDH) n ultrathin films (UTFs) via a layer-by-layer assembly technique based on electrostatic and hydrogen-bond interactions, and this realized the immobilization of EGFP. The obtained UTFs show a long-range-ordered periodic layered stacking structure and strong fluorescence originating from EGFP, which also retains its predominant β-barrel structure well in the LDH laminates. The inorganic LDH laminates play an important role in protecting and improving the structure and properties of the EGFP in the UTFs. Furthermore, the UTFs exhibit a reversible fluorescence response between different pH environments or different wet or dry environments, and also could detect some small biological medicine molecules such as protoporphyrin, and thus they have the potential to be a novel type of biological fluorescence sensor.

A highly integrated nanocomposite is constructed based on mesoporous silica nanotubes (SiNTs)-loaded with Mn 3 O 4 nanoparticles for cervical cancer therapy via T 1 -weighted magnetic resonance imaging and doxorubicin-based chemotherapy. Mn 3 O 4 magnetic nanoparticles uniformly distributed within SiNTs can effectively detect the tumor microenvironment, as revealed by clinical T 1 -weighted magnetic resonance imaging. The SiNTs possessed a high loading rate for doxorubicin (DOX) and a simultaneous pH-dependent response release, mainly due to the electrostatic interaction between DOX molecules and the mesoporous silica surface. According to MTT assay, confocal laser scanning microscopy and bio-TEM observations, the cellular uptake of the as-prepared DOX-Mn 3 O 4 -SiNTs was both dose- and time-dependent, and the SiNTs were accumulated mostly in lysosomes. Further pathological examinations revealed that the DOX-Mn 3 O 4 -SiNTs multifunctional drug delivery system led to remarkably destructed cells, large vacuoles, and irregular widening of tumor tissues. This collaborative strategy could pave the way towards high-performance nanotherapeutics with superior antitumor efficacy and reduced side effects.

Nanoclay can be incorporated into emerging dual functional drug delivery systems (DDSs) to promote efficiency in drug delivery and reduce the toxicity of doxorubicin (DOX) used for thyroid cancer treatment. This paper reports the expansion of the basal spacing of kaolinite nanoclay was expanded from 0.72 nm to 0.85 nm, which could provide sufficiently spacious site for hosting doxorubicin molecules and controlling the diffusion rate. A targeted design for papillary thyroid cancer cells was achieved by introducing KI, which is consumed by the sodium-iodide symporter (NIS). As indicated by MTT assays, confocal laser scanning microscopy and bio-TEM observations, methoxy-intercalated kaolinite (KaolinMeOH) exhibited negligible cytotoxicity against papillary thyroid cancer cells. By contrast, DOX-KaolinMeOH showed dose-dependent therapeutic effects in vitro, and KI@DOX-KaolinMeOH was found to act as a powerful targeted therapeutic drug. Furthermore, active and passive targeting strategies played a role in the accumulation of the drug molecules, as verified by an in vivo bio-distribution analysis.

DNA triplex assembly has attracted a variety of interest in the regulation of genetic expression, drug screening, molecular switches, and sensors. However, these achievements are essentially dependent on the formation and stability of the triplex assembly. Herein, the recognition of DNA triplex assembly with various isoquinoline alkaloids was investigated. We found that natural chelerythrine (CHE) exhibits the highest selectivity in recognizing the triplex structure. The DNA triplex stability is substantially increased upon CHE binding, as opposed to the invariance in the stability of the duplex counterpart. CHE also favors the assembly of the triplex-forming oligonucleotide (TFO) with its duplex counterpart. The triplex binding switches CHE to a strong fluorescent emitter, which suggests CHE as a useful probe in following triplex assembly. As a unique triplex selector, inducer, and emitter, CHE successfully reports the wide pH- and metal-ion-dependent tunability of the triplex nanoswitch in a label-free manner., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Atomic force microscopy was employed to measure the colloidal interactions between silicon nitride cantilever tips and scheelite crystal surfaces in 1 mM KCl solutions of varying pH. By fitting the Derjguin-Landau-Verwey-Overbeek (DLVO) theoretical model to the recorded force-distance curves, the surface-charge density and surface-potential values were calculated for three crystallographic surfaces including {112}, {101}, and {001}. The calculated surface-potential values were negative in both acidic and basic solutions and varied among crystallographic surfaces. The determined surface-potential values were within zeta-potential values reported in the literature for powdered scheelite minerals. The surface {101} was the most negatively charged surface, followed by {112} and {001}. The surface potential for {001} was only slightly affected by pH, whereas the surface potential for both {112} and {101} increased with increasing pH. Anisotropy in surface-charge density was analyzed in relation to the surface density of active oxygen atoms, that is, the density of oxygen atoms with one or two broken bond(s) within tungstate ions located in the topmost surface layer. On a surface with a higher surface density of active oxygen atoms, a larger number of OH(-) are expected to adsorb through hydrogen bonding, leading to a more negatively charged surface.