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Developing highly active and stable nanocarbon catalysts for selective oxidation reactions has attracted much attention due to their potential as an alternative to traditional metal-based or noble metal catalysts. However, the nature of active sites and the reaction mechanism of nanocarbon catalysts for oxidation reactions still remains largely unknown, which hinders the rational design and development of highly efficient carbon-based catalysts. Here we report a facile strategy for the synthesis of boron and nitrogen co-doped carbon nanosheet material (BNC), which exhibits excellent catalytic activity with 91% conversion and 99% selectivity in selective oxidation of benzyl alcohol into benzaldehyde, superior to those of traditional carbon materials (oxidized carbon nanotubes, graphites and commercial nanocarbons). Structural characterizations and kinetic measurements are studied to clarify the active site, in which phenolic hydroxyl on BNC is responsible for the production of benzaldehyde. Meanwhile, we put forward a possible reaction mechanism and point out the key factors in determining the reactivity for this reaction. Therefore, the present work provides new insight into structure–function relationships, paving the way for the development of highly efficient nanocarbon catalysts.

The borocarbonitrides (BCNs) have exhibited enormous potential as non-metallic catalysts for alkane oxidative dehydrogenation (ODH) reactions. However, the poor electron transportation ability in BCN leads to a low reactivity of oxygen functional groups (–C=O and –B–OH). Herein, we present a generalized strategy to promote the catalytic activity of BCN through in situ encapsulation of transition-metal (Fe, Co, Ni) nanoparticles within BCN nanotubes (BCNNTs). Among them, individual metal particles themselves do not contribute directly on ODH reactions and mainly serve as electron modulators to tune the electron density of –C=O and –B–OH active sites on BCNNTs. As a result, catalytic activities of all metal@BCNNTs catalysts surpass pure BCN in ethylbenzene (EB) ODH reactions, among which Fe@BCNNTs displays a significant activity enhancement with 36% EB conversion with the styrene (ST) selectivity remaining >98% under gentle reaction conditions. Structural and kinetic analyses proved that the promotion effect originated from the strong interactions between metal nanoparticles and BCNNTs. The theoretical calculations disclosed that the enhanced ODH activity was due to the electron transfer from the encapsulated metal to BCNNTs, which increases the electron transportation ability and electron density of BCNNTs, thus promoting the nucleophilicity of –C=O and –B–OH active sites, leading to the reduced activation energy barrier for –C–H bond dissociation. The present work sets forth the structure-function relationship, identifying opportunities for rational design of highly efficient BCN catalysts for ODH reactions.

A new strategy based on the graphite phase carbon nitride/non-integral bismuth oxychloride/bismuth oxybromide (g-C3N4/BiOCl0.5Br0.5) heterojunction and the plasma resonance effect of gold nanoparticles (AuNPs) was developed to construct a novel AuNPs/g-C3N4/BiOCl0.5Br0.5/ITO sensitized photoelectrochemical sensor for rapid and sensitive detection of plant hormone 2-chloroethyl phosphate (ETH). The morphology structure of the as-prepared materials and the characteristics of electrode film were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS), and the photoelectrochemical response to ETH of the sensor was studied by electrochemical impedance spectroscopy (EIS) and current-time curve (i-t), etc. Density functional theory (DFT) was used to calculate the charge density of atoms in the g-C3N4/BiOCl0.5Br0.5 heterojunction, the electronic transition mechanism was analyzed, and the sensor's sensitization mechanism was further proposed. Furthermore, the relationship between the change of the sensor's transient current and the concentration of ETH was studied. Under the optimal conditions, ETH concentration in the range of 20.00 nmol/L–63.00 μmol/L had a good linear relationship with photocurrent, and the AuNPs/g-C3N4/BiOCl0.5Br0.5/ITO sensor exhibited high stability and high reproducibility. This study provided a feasible solution for the rapid and efficient detection of ETH, as well as a new sensing platform for detection of other plant hormones.

A BiFeO3/TiO2 p-n heterojunction photocatalyst with ferroelectric synergistic effect under visible-light irradiation was developed through facile hydrolysis and precipitation by forming nanospheres of TiO2 on BiFeO3 nanocube to improve the photocatalytic efficiency. Analyses of the microstructure, optical properties, and photoelectrochemical performance indicate the formation of a core–shell heterostructure of BiFeO3/TiO2 with excellent energy band matching. The BiFeO3/TiO2 p-n heterojunction has enlarged specific surface area, higher sensitivity to visible-light, and improved separation and transfer efficiency of photoelectron-hole pairs than single TiO2 and BiFeO3. Moreover, the composite exhibits superior photocatalytic degradation performance for methylene blue (MB) and common antibiotic tetracycline (TC) under UV and visible-light irradiation. The MB degradation rate within 180 min reaches 78.4% and 90.4% under UV and visible-light irradiation, respectively. Furthermore, the enhanced photocatalytic mechanism of BiFeO3/TiO2 is explored by photoluminescence (PL), electrochemical impedance spectroscopy (EIS), transient photocurrent analysis, radical quenching, and band structure characterization.

Background Self-reported tobacco pack-year history plays a large role in decisions about low-dose CT screening for lung cancer, yet is challenging to measure accurately. Research Question To what extent does random measurement error in pack-year information impact screening decisions and screening effectiveness? Study Design and Methods Retrospective cohort study of 10,449 patients with pack-year history documented at least twice between October 2013 and July 2017 across 8 academic Veterans Affairs sites. Outcome measures included (1) observed reliability of pack-year information based on all repeat measures for the study population and (2) each person’s statistically “true” pack-year information based on best linear unbiased predictor from a multilevel linear random effects model. To examine how unreliability leads to misclassification of screening eligibility and inaccuracy in estimating lung cancer risk, we simulated pack-year observations for each person, first comparing simulated pack-year and lung cancer risk values with true values, then comparing outcomes when basing screening decisions on unreliable pack-year information vs true information. Results Reliability of assessing pack-year information in routine practice varied across sites. Thus, we examined the clinical impact of two different levels of reliability, based on the range of intraclass correlation coefficients observed. Using a ≥ 30-pack-year threshold led to a high rate of eligibility misclassifications (48.1% misclassified with higher reliability pack-year information and 60.7% misclassified with lower reliability information). However, using a lung cancer risk threshold leads to fewer misclassifications (47.3%-49.7% misclassified when using lower reliability pack-year information) and maintains screening effectiveness better when using unreliable pack-year information. Interpretation Random error in real-world pack-year assessments leads to a substantial rate of misclassifying who should be offered CT screening if a ≥ 30-pack-year criterion is used. However, using a lung cancer risk threshold mitigates the impact of unreliable pack-year information. Decision-makers concerned about the impact of unreliable pack-year information should consider using risk-based approaches to CT screening.

The Gudui geothermal field records the highest temperature at equivalent borehole depths among the mainland hydrothermal systems in mainland China. Located about 150 ​km southeast of Lhasa City, the capital of Tibet, the Gudui geothermal field belongs to the Sangri–Cuona rift belt, also known as the Sangri–Cuona geothermal belt, and is representative of the non-volcanic geothermal systems in the Himalayas. In this study, oxygen-18 and deuterium isotope compositions as well as 87Sr/86Sr ratios of water samples collected from the Gudui geothermal field were characterized to understand the origin and mixing processes of the geothermal fluids at Gudui. Hydrogen and oxygen isotope plots show both, deep and shallow reservoirs in the Gudui geothermal field. Deep geothermal fluids are the mixing product of magmatic and infiltrating snow-melt water. Calculations show that the magma fluid component of the deep geothermal fluids account for about 21.10%–24.04%; magma fluids may also be a contributing source of lithium. The linear relationship of the 87Sr/86Sr isotopic ratio versus the 1/Sr plot indicates that shallow geothermal fluids form from the mixing of deep geothermal fluids with cold groundwater. Using a binary mixing model with deep geothermal fluid and cold groundwater as two end-members, the mixing ratios of the latter in most surface hot springs samples were calculated to be between 5% and 10%. Combined with basic geological characteristics, hydrogen and oxygen isotope characteristics, strontium concentration, 87Sr/86Sr ratios, and the binary mixing model, we infer the 6th-Class Reservoirs Evolution Conceptual Model (6-CRECM) for the Gudui geothermal system. This model represents an idealized summary of the characteristics of the Gudui geothermal field based on our comprehensive understanding of the origin and mixing processes of the geothermal fluid in Gudui. This study may aid in identifying the geothermal and geochemical origin of the Gudui high-temperature hydrothermal systems in remote Tibet of China, whose potential for geothermal development and utilization is enormous and untapped.

Objective The rise of carbapenem resistance among Acinetobacter baumannii represents a challenge for the therapeutic management of infections. The present study aimed to investigate the sequence types and carbapenem resistance in A. baumannii strains collected from various clinical specimens from the patients admitted to tertiary care hospitals in Pakistan. Methods A total of 156 A. baumannii clinical strains were analyzed for antimicrobial susceptibility, followed by genetic screening for the carbapenem-resistant determinants. All the A. baumannii strains were typed using multilocus sequence typing by the Pasteur scheme. Results One thirty-nine of the 156 isolates (89.1%) were carbapenem-resistant and out of these 136 carried the blaOXA-23-like genes. Interestingly the sequence type (ST) 589 was the most common sequence type that was classified as clonal complex 1 (CC1). The ST2 was the second most common sequence type that corresponds to the clonal complex 2/92 (Pasteur scheme/oxford scheme), however, it was distributed in all the hospitals. Conclusion The diverse clones of carbapenem-resistant A. baumannii including the already reported STs as well as new STs carrying OXA-23 are mainly distributed in Pakistan. This is the first study that described the molecular epidemiology of widely disseminated A. baumannii in Pakistan. The findings will help to improve the knowledge of predominant sequence types and will be valuable for the deeper understanding of resistance mechanisms among various MLST types.

Summary In situ modulation of surface reaction is a powerful approach to drive high-yield H2O2 electrosynthesis on metal-free carbon. Here, we discover that cationic surfactants can work efficiently as an in situ kinetic promoter for the oxygen-to-peroxide reaction on a carbon black electrode, achieving a peroxide yield above 90% (up to 95.2%) across a >0.8 V window in alkaline media, the best among reported H2O2 electrocatalysts. Our characterizations and kinetic model analysis show that the high peroxide selectivity is attributable to surface carboxylates (–COO−) with weak peroxide binding under a Coulombic pull imposed by an adsorbed cationic layer. Although surface carbonyls (–C=O) also participate in the peroxide synthesis, they exhibit strong binding to peroxide and promote on-site reduction at moderate-to-high overpotential. At only a minute amount of cationic surfactant, a chronoamperometry experiment with a carbonyl-free system can deliver a peroxide production at a sustainably high selectivity (∼96%) over 10 h.

We report herein the design of a novel electrochemical sensing strategy for sensitive detection of pesticide based on graphitic carbon nitride (g-C3N4)/graphene oxide(GO) nanocomposite covalently bound to a ferrocene containing dendrimer(Fc-TED). The g-C3N4 with sufficient N atoms for providing lone pairs of electrons to an electron acceptor so as to enhance the adsorption towards organic molecules. The Fc-TED dendrimers with the native redox signaling center (Fe3+/Fe2+) can increase the electron transition of g-C3N4 from valence to conduction band. While GO can accelerate the electron transfer from g-C3N4 surface and Fc-TED to glassy carbon electrode(GCE), which would amplify the electrochemical signal of g-C3N4/GO/Fc-TED/GCE sensor and then improve the sensing performance. It is found that the fabricated electrode demonstrated an admirable electrochemical sensing performance towards metolcarb in terms of low detection limit (8.3 nM), wide concentration range (0.045–213 μM) and rapid response time (2s). The proposed sensor can selectively detect the metolcarb and easily discriminated metolcarb from the possible interfering species. The practical applicability of the sensor was successfully evaluated in real vegetable sample and achieved satisfactory recoveries with good precision and accuracy.

The flowability of microcrystalline cellulose is related to its particle morphology and structure, but this relation is difficult to characterize quantitatively, due to irregularity in particle shape. This study uses fractal dimension combined with shape factors (circularity, elongation, compactness, solidity) for characterization of six microcrystalline cellulose (MCC) powder samples of different particle morphology. Fractal dimension was shown to be the main factor affecting the powder flowability. The K-means clustering method and box plot were used to analyze the morphological differences of three types of MCC particles with large flowability differences as well as small flowability differences with large size differences. Among the four shape factors, circularity was shown to exert the greatest influence on powder flowability. Validating these results, a thorough statistical multivariate regression analysis was conducted. This treatment eliminated the other shape factors, to yield a two-parameter equation characterizing the quantitative relationship between the MCC powder flowability and morphology.

Dysphagia is one of the common complications after stroke. Dysphagia significantly increases the probability of serious adverse consequences. The purpose of this study was to compare the characteristics of submental muscles electromyography and hyoid motion parameters between patients with dysphagia after stroke and healthy controls, and whether there is a synergistic effect between the function of the submental muscles and the movement of the hyoid.Fifteen patients with post-stroke dysphagia and fifteen healthy adults simultaneously underwent the videofluoroscopic and surface electromyography of the submental muscles while swallowing 5 ml of concentrated liquid barium sulphate. The electromyographic signal of the submental muscles was analysed along with parameters of hyoid movement.Stage transition duration and duration of surface electromyographic activity were extended significantly in post-stroke dysphagia patients(P 0.05). Surface electromyography amplitude and hyoid movement were significantly reduced in patients (P 0.05). There was a significant correlation between the maximum hyoid movement distance and the peak sEMG amplitude in healthy controls (r = 0.660, P = 0.014), but not in patients with dysphagia after stroke (r = 0.425, P = 0.148).Submental muscles electromyographic signal changes in patients may be the result of uncoordinated muscle contractions and decreased muscle strength. Furthermore, the reduced hyoid movement distance may be due to impaired function of the submental muscles. In addition, the submental muscles and hyoid movement or other swallowing structures functions were impaired to varying degrees, resulting in the disappearance of the correlation between the maximum movement distance of the hyoid and the peak amplitude.

To develop a full-biodegradable thermoresponsive polymer with a wide temperature range, a hydrophilic, biodegradable and biocompatible thermoresponsive polymer having a polylactide backbone polymer and a side chain norbornene group was synthesized by ring-opening polymerization of a norbornene-functionalized lactide, followed by graft of backbone polymer with polyethylene glycol monomethyl ether (MPEG) and modification with isopropylamide (IPA), the latter of which critically influences the phase transition temperature of the copolymer. The effects of polymerization degree (DP), molecular weight of MPEG, the proportion of MPEG and IPA, and the concentration of polymer on the behaviors of the thermoresponsive polymer solution were systematically studied. The Cp ranged from 32 to 72 °C, and it was found that higher number of the MPEG moiety led to higher Cp, whereas the longer isopropylamide group resulted in lower Cp. It is noteworthy that with the unique characteristics, thermosensitivity at body temperature, biodegradability, and a well-defined copolymer structure, the developed thermoresponsive polymer is promising for biomedical applications as an essential material.

A new comprehensive utilization of vanadium slag (VS) method focusing on inhibiting leaching of iron (Fe) during the leaching of vanadium (V) using sulfuric acid (SA) was proposed. In this process, Cr2O3 was added to VS to conjugate with Fe in the VS to form (Fex,Cr1-x)2O3 which is insoluble in SA, resulting in the decrease of leaching ratio (LR) of Fe to avoid the subsequent separation difficulty of V in leachate. The phase evolutions of VS during the roasting and SA leaching process, and the influences of roasting temperature, roasting time, and addition of Cr2O3 on the LR of V, Fe and chromium (Cr) from VS were studied. When the addition of Cr2O3 is 12 wt.%, the mass concentration of V in the leachate is 1 order magnitude higher than Fe and the mass ratio of V to Fe reaches 18.34. The LR of V, Fe and Cr are 91% 1.39% and 0.28%, respectively. The leaching residue can be reused as ironmaking raw material. More importantly, the (Fex,Cr1-x)2O3 and Fe2TiO5 can be separated from the leaching residue and recycled as raw materials for black ceramic pigments and titanium dioxide production by mineral processing technology, respectively.

Iron and nitrogen co-doped carbons show great potential for high-performance electrochemical oxygen reduction reaction. However, the rational design of atomically dispersed iron over nitrogen-doped carbons with activity comparable to that of Pt-C is still challenging. Herein, we develop a new approach that enables the direct formation of intrinsically nitrogen-functionalized two-dimensional sheet-like carbons containing a high concentration of single Fe atoms. This strategy only involves one-step pyrolysis of both, guanine and iron nitrate, without using any guiding agent and sacrificial template. The electrochemistry tests demonstrate an excellent ORR performance of the prepared Fe-Nx-C catalyst with a half-wave potential of 0.85 V and a limited current density of −6.5 mA/cm2 in alkaline medium, outperforming the commercial Pt-C and most of previously reported Fe-Nx-C catalysts. We believe that the emergence of superior ORR performance is mostly attributed to the uniform dispersion of single Fe atoms at the molecular level and the formation of abundant coordinated Fe-Nx sites. In addition, the high surface area, optimal porosity and defective structure (particularly the defects at the edge) of the two-dimensional carbons are also beneficial for the improved ORR activity.

Low-density foams based on nanofibrillated cellulose (NFC) made from Pinus massoniane softwood pulp were prepared from NFC aqueous suspensions containing one of four C2–C4 alcohols followed by freeze-drying, with the goal of controlling their pore structure and reducing the shrink rate. The foams prepared from NFC suspensions containing ethanol, isopropanol and n-butanol exhibited highly porous structures with a honeycomb-like cellular texture featuring well-defined “cell walls” between the layers. By contrast, the tert-butanol/NFC foam featured a higher number of smaller size pores with irregular shape. The foams prepared by freezing at −196 °C with ethanol also revealed small size pores, with no layered pore structure. The results obtained suggested that freeze-drying could be used to control the key foam parameters by adding different alcohols into an NFC suspension and adjusting the freezing temperature. Combining the obtained information, a possible formation mechanism was proposed. The microstructure, density, porosity, shrinkage, mechanical properties and thermal properties of NFC foams were determined. The obtained NFC foams feature low shrinkage upon formation and thermal conductivity. Smaller Young’s modulus and energy absorption yet similar yield stress values compared to the blank indicate that the freeze-drying in the presence of alcohols tends to generate “soft” foams.

Nanofibrillated cellulose (NFC)-based foam materials have broad prospects in replacing traditional foams, due to its facile natural biodegradation. This study addressed the relationship between the foam preparation process parameters and resulting pore structure. An aqueous NFC suspension was freeze-dried while adding an organic solvent, ethanol, to adjust the curing process. The effects of the solid content and freeze-drying temperature on the microstructure and mechanical stability as well as heat transfer performance of the produced NFC-based foam were investigated. The foam obtained at a 3%–5% solid content featured a well-defined lamellar and interlayer pillar support structure. With an increase in the solid content, the average wall thickness increased whereas the average pore area decreased. Yet the pore density increased with the pore distribution becoming non-uniform. With a decrease in freezing temperature, the wall thickness decreased (with no wall structure at −196 °C) but the pore density increased, with the pores being distributed more uniformly. The foam mechanical strength and thermal conductivity were found to be linked to porosity. The foam material had the most suitable mechanical and thermal insulation properties when prepared with a 5% solid content at a freeze-drying temperature of −55 °C.

Direct-determination is a fast and free of contamination method for analysis of substances in water samples. However, direct-determination of SO

With the increase of electromagnetic radiation pollution, there is an urgent need to develop lightweight, ultra-thin, and high electromagnetic shielding composite film to eliminate unwanted electromagnetic interference. Herein, based on the layer-by-layer assembly strategy, a simple solution dip coating method was used to achieve the combination of two-dimensional transition metal (MXene) and nanofiber film, thereby constructing a conductive composite film with a unique undulating structure. The silicon-containing hydrophobic layer imparted excellent hydrophobic properties to the composite film while maintained the stability of the sandwich structure. The contact angle (CA) of the composite film with ultra-thin thickness (29um) was 125.49° and the conductivity was as high as 71.91 S/cm. The hydrophobic treatment would not damage the flexibility and mechanical properties of the composite film. In particular, the average shielding effectiveness (SE) and SSE/t could as high as 28.82 dB and 12422.41 dB cm2g−1, due to the layered structure formed by the connection of countless MXene nanosheets is beneficial to promote multiple absorption and reflection. This layer-by-layer assembly strategy provides a facile route in fabricating light-weight, flexible and ultrathin composite film for high-performance electromagnetic shielding, which is of great significance for broadening the practical application of MXene-based conductive materials.

Water was the source of life, in order to solve the serious water pollution problem facing the world, researchers have proposed many solutions. Among them, photoelectric catalytic technology based on semiconductor materials was an ideal and sustainable solution. Herein, by combining successive ionic layer adsorption and reaction (SILAR) with sol-gel electrospinning two strategies, a novel S-scheme heterojunction based on flexible and hierarchical BiOI/TiO2 nanofibrous membranes (BiOI/TiO2 NFM) was fabricated. The degradation rates of tetracycline (TC) and Rhodamine B (RHB) were 98.7% and 95.6%, respectively, under visible light irradiation. The main reason, except for the benefits offered by the hierarchical nanofiber structure, such as the large surface area, tightly connected interfaces and more exposed active sites, other advantages derived from photogenerated carrier transfer and superior redox ability were also momentous. To reveal the formed S-scheme heterojunction, a variety of test methods were used to characterize and test. These studies showed a significant increase in charge separation efficiency in the BiOI/TiO2 NFM, and the charge transport of S-scheme heterojunction was demonstrated. This study may offer new design ideas for the design and construction of novel structures of S-scheme heterojunctions.

A multi-stage electrochemical method was developed to synthesize palladium (Pd) nanoparticles supported on hydroxyapatite (HA) coatings. In the first stage, a dense coating of HA nanocrystals was synthesized from an aqueous electrolyte solution onto a titanium cathode surface through a galvanostatic process. The HA-coated titanium electrode was then used as the cathode for the electrochemical reduction of Pd2+ from aqueous solution. A synthesis approach using two sequential electrochemical reduction reactions was found to be more effective in producing uniform coatings of Pd nanoparticles than a single stage reduction. In the first step, a higher voltage was applied to the cathode for a short time to promote the nucleation of Pd nanoparticles. A lower voltage was then applied for a longer time in the second stage to promote the growth of the Pd nanoparticles. The size and size distribution of the Pd nanoparticles were controlled by adjusting the duration of the first and second stages of electrochemical reduction. The resulting HA supported Pd nanoparticles demonstrated significantly higher catalytic activity than commercial Pd nanoparticles in the degradation of methyl orange by NaBH4. The high surface area and the complex oxidation states of the HA-supported Pd nanoparticles are believed to account for the enhanced catalytic activity.

Podophyllotoxin (PPT) is a chemotherapeutic agent which has shown significant activity against P-glycoprotein (P-gp) mediated multi drug resistant cancer cells. However, because of the poor aqueous solubility and high toxicity, PPT cannot be used in clinical cancer therapy. In order to enhance the efficiency and reduce side effect of PPT, a polypeptide based PPT conjugate PLG-g-mPEG-PPT was developed and used for the treatment of multi drug resistant breast cancer. The PLG-g-mPEG-PPT was prepared by conjugating PPT to poly( l -glutamic acid)-g-methoxy poly(ethylene glycol) (PLG-g-mPEG) via ester bonds. The PPT conjugates self-assembled into nanoparticles with average sizes about 100 nm in aqueous solution. Western blotting assay showed that the PLG-g-mPEG-PPT could effectively inhibit the expression of P-gp in the multiple drug resistant MCF-7/ADR cells. In vitro cytotoxicity assay indicated that the resistance index (RI) values of PLG-g-mPEG-PPT on different drug-resistant cancer cell lines exhibited 57–270 folds reduction than of traditional microtubule inhibitor chemotherapeutic drug PTX or DTX. Hemolysis assay demonstrated that the conjugation greatly decreased the hemolytic activity of free PPT. Maximum tolerated dose (MTD) of PLG-g-mPEG-PPT increased greatly (13.3 folds) as compared to that of free PPT. In vivo study showed that the PLG-g-mPEG-PPT conjugate remarkably enhanced the antitumor efficacy against MCF-7/ADR xenograft tumors with a tumor suppression rate (TSR) of 82.5%, displayed significantly improved anticancer efficacy as compared to free PPT (TSR = 37.1%) with minimal toxicity when both of the two formulations were used in MTD. Statement of Significance The development of multiple drug resistance (MDR) of cancer cells is the main cause of chemotherapy failure. The over-expression of P-glycoprotein (P-gp) has been recognized to be the most important cause of MDR in cancer. Podophyllotoxin (PPT) is a chemotherapeutic agent which has shown strong activity against P-gp mediated multidrug resistant cancer cells by simultaneously inhibiting the over-expression of P-gp and the growth of cancer cells. However, PPT can not be used in clinical cancer treatment due to its poor aqueous solubility and high toxicity. Herein, we developed a polypeptide based PPT conjugate PLG-g-mPEG-PPT by conjugating PPT to poly( l -glutamic acid)-g-methoxy poly(ethylene glycol). The PLG-g-mPEG-PPT shows significantly decreased hemolytic activity, greatly improved maximum tolerated dose and remarkably enhanced antitumor efficacy against MCF-7/ADR xenograft tumors as compared to free PPT.

The traditional chemotherapy using single agent may suffer from serious drawbacks, particularly dose-limiting toxicity and relatively low antitumor efficacy, which can lead to failure of chemotherapy. Co-delivery of two or more therapeutic drugs in nanotechnology is a potential strategy to generate synergistic anticancer effects and reduce individual drug-related toxicity, but explosive release of each drug from multi-drug loaded nanoparticles has been a distinct obstacle. In this study, a novel amphiphilic and biodegradable triblock copolymer, named MPEG-b-norbornene functional PLA-b-P(α-BrCL), was constructed to covalently conjugate dual anticancer drugs, i.e., doxorubicin (DOX) and paclitaxel (PTX). The resultant P-PTX-DOX prodrugs were confirmed by 1H NMR and HPLC. By adjusting the length of PLA and PCL, it was shown that this polymer could carry relatively sufficient amount of both drugs (12.1 wt% of PTX and 15.8 wt% of DOX, respectively). Moreover, the drug release profile of P-PTX-DOX in vitro was also analyzed, which showed the desired drug release in a sustained manner. Cytotoxicity study indicated synergistic effects of P-PTX-DOX self-assembled micelles in suppression of proliferation of A549 cancer cells. In summary, a novel polyester-based copolymer was developed to covalently conjugate dual-drug, which exhibited controlled drug release behavior and synergistic anti-cancer efficacy in vitro.

A novel resource utilization of the calcium-based semi-dry flue gas desulfurization ash is investigated. In the present study, the semi-dry desulfurization ash is used as a reductant for chromium and vanadium removal by chemical reduction precipitation, the byproduct gypsum and chromium-contained sludge are obtained. Besides, the effects of main operational parameters (reaction pH, desulfurization ash dosage and reaction time) on the heavy metal removal are investigated, and the main reaction mechanism for this treatment technology is also proposed. Under the optimal conditions, the residual concentrations of Cr(VI), total Cr and V are 0.163mg/L, 0.395mg/L and 0.155mg/L, respectively. Additionally, byproduct gypsum and chromium-contained sludge are characterized using X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR), scanning electron microscope-energy dispersive spectrometer (SEM-EDS) and thermogravimetry differential scanning calorimetry (TG-DSC), respectively. Finally, the resource utilization methods of the byproduct gypsum and chromium-contained sludge from this technology are also submitted. The byproduct gypsum can be utilized to produce hemihydrate calcium sulfate whisker, and the roasted heavy metal precipitation can be used as a primary chromium raw material (Cr2O3 content is about 83%).

Human body microenvironment adaptive power generator with multifunction is attractive for the development of portable wearable devices. Here, a PEDOT-based photo-thermoelectric textile is developed via a two-step strategy, where the PDA is introduced to induce PEDOT to form the hierarchical structure. Thus, the top surface of the PEDOT-based textile owns the excellent thermoelectric performance (PF = 88.70 nW/(m•K2)), and the bottom surface holds a great photothermal effect that can reach about 80 °C under 175w IR light. In addition, the PEDOT-based textile has 51.87% of solar conversion efficiency under 3 sun. A assembled textile solar panel fabricated by the sewing method renders a voltage output of 1.37 mV under 500w illumination. Interestingly, with the synergistic work of photo-thermoelectric and hydroelectric effects, the wetted textile solar panel can produce a voltage of ~ 12.5 mV and a power of 9.81 μW under 500 W illumination. Meanwhile, it can also generate the solar steam of ~ 3 g within 1 h. Therefore, such wet textile solar panels can harvest solar energy and generate solar steam at the same time, which provides a route to fabricate a smart wearable energy harvester that can be used for human body humidity management.