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Green human resource management (GHRM) determines the green behavior practice of employees and affects the social environment and the realization of “Beautiful China” and “Green Development”. In this study, to explore the impact mechanism of GHRM on employees’ green behavior, employees at all levels in an enterprise were selected to be research subjects and a regulated intermediary model was established, based on social exchange theory and the individual-environment matching theory. This paper investigated the enterprise’s GHRM, personal green behavior, relational psychological contract, environmental knowledge and green values. The results show that GHRM has a significant positive predictive effect on employees’ green behavior, the relational psychological contract plays an intermediary role between GHRM and employees’ green behavior and the intermediary role of the relational psychological contract is regulated by environmental knowledge and green values. These research results explain the relationship between GHRM and employees’ green behavior and provide an important basis for enterprises to implement GHRM practice and promote employees’ green behavior.

To examine the safety of Chinese traditional fermented fish products (CTFPs) available on the Chinese market, nitrite, nitrate, biogenic amines (BAs) and volatile N-nitrosamines (VNAs) content in 33 commercial CTFPs from different provinces was investigated. The mean content of nitrite and nitrate wase 0.63 and 749.5 mg/kg, respectively. Concerning the occurrence of BAs, the accumulation in all CTFPs samples remained at low levels, whereas only in one sample from Guangxi the histamine content exceeded the critical level (50 mg/kg). In addition, six types of VNAs, including N-nitrosodimethylamine (NDMA), N-nitrosoethylmethylamine, N-nitrosopiperidine, N-nitrosopyrrolidine, N-nitrosomorpholine and N-nitrosodiphenylamine, were detected in a high number of samples. The NDMA content in 36.4% of the samples and the total VNAs content in about 63.6% of the samples were unacceptable. Principal component analysis indicated that the accumulation of NDMA and total VNAs was closely related with the content of histamine, tyramine and nitrate.

The electrochemical reduction of carbon dioxide (CO2) to chemical feedstocks is an attractive method for the removal of CO2 from the environment. Although copper (Cu)-based catalysts produce hydroc...

Utilization of carbon dioxide (CO2) is of great significance in the development of CO2 absorption and the solution of greenhouse gas effect. Highly efficient conversion of CO2 into cyclic carbonate with green catalysts is essential for the more sustainable expansion of CO2 fixation. Traditional batch reactor is limited by low efficiency, high cost and low security. Meanwhile, continuous flow system showcased a myriad of virtues, including shortening the residence time from hours to seconds, and decreasing reaction temperature, and possessing the nature of easy industrial scale-up. In this paper, a continuous-flow microreaction system was developed to synthesis propylene carbonate (PC) from propylene oxide (PO) and CO2 using 1-butyl-3-methylimidazolium bromide ([BMIM]Br) as catalyst. By observing the flow patterns inside microreaction system, the effects of reaction temperature, molar fraction of catalyst, operating pressure, residence time, molar ratio of CO2/PO as well as recycling performance of catalyst on the overall performances were comprehensively evaluated into details. Under different reaction conditions, the flow patterns were set to vary between slug flow and annular flow. The results showed that the yield of propylene carbonate (PC) can reach 99.7% at 140 °C and 3.0 MPa with the residence time of 166 s, while the recycling performance of the designed system greatly conforms the future trend of green chemistry.

Iron-incorporated ordered carbonaceous frameworks (OCFs) have been synthesized by the pyrolysis of iron porphyrin with ethynyl groups as polymerizable/carbonizable moieties at a temperature higher than 600 °C. The pyrolysis behavior is analyzed by thermogravimetry-differential thermal analysis-mass spectrometry, and the obtained carbon materials are characterized by X-ray diffraction, X-ray absorption fine structure, and high-angle annular dark-field scanning transmission electron microscopy. The introduction of ethynyl groups at the meta positions of the peripheral phenyl groups is essential for efficient cross-linking upon thermal polymerization. The thermally stable polymer thus obtained can be transformed into OCFs with high carbonization yield of 93 % at the subsequent carbonization. OCFs possess periodic structural regularity and porphyrin Fe-N4 coordination structure, and exhibit electrocatalysis for the conversion of CO2 into CO.

Subsurface biological processes, such as biofilm development, modify flow and permeability in fractured rocks, greatly impacting energy production or treatment efficiencies. This study aims to understand biological–hydrological interactions at a bench scale during the progression and treatment of souring (microbially mediated sulfide production). Few bench-scale studies investigate the role of a biofilm on the flow and permeability evolution, sulfidogensis, and nitrate treatment efficacy in fractured rocks. Our experiment consisted of three sandstone columns that represent differing fracture characteristics due to the mode of fracture initiation: one column with no fracture (as a control), one column with a sawcut fracture, and a third column with a fracture induced by Brazilian loading (tensile). We seek to understand the effects of the biofilm-permeability feedback on flow and nutrient transport characteristics of fractured rocks; specifically, we (1) demonstrate how fracture geometries impact the development of the biomass-permeability feedback within the rock fractures and (2) observe the souring trajectory and effects of nitrate treatment. Observed permeability trends demonstrated that bioclogging modified the flow properties of fractured columns such that they became hydrologically similar to those of the control column. While fractures were initially the main sites of sulfate reduction, when fractures were clogged, the flow in the fractured columns transitioned from a fracture-dominated flow to a matrix-dominated flow, impacting the delivery of an electron acceptor/donor to the microbial population, reducing sulfate reduction rates. Experimental data also demonstrated two distinct stages in the biofilm-permeability development. During the initial biofilm development stage, the growing microbial population had increased reaction rates but decreased permeability, i.e., a negative correlation between reaction rates and permeability. In the later stage, when the biofilm had clogged the columns, a series of biofilm shedding and regrowth directly led to reopening and clogging of the flow channels, affecting microbial accessibility to limiting nutrients. As such, a positive correlation between reaction rates and permeability was observed in this later stage. Post experimental measurements of surface elevations of the fractured surfaces revealed that surface elevations in the sawcut column were lower and more evenly distributed than the surface elevations in the tensile column where the more unevenly fractured surfaces potentially better supported the microbial establishment.

Global warming and climate change due to anthropogenic carbon dioxide (CO2) have aroused significant concerns at the global scale due to rapid economic growth in industries and other fields. Therefore, CO2 capture, use, and storage have become particularly important. In this review, general background and methods for CO2 capture and separation, in particular, on ionic liquids (ILs)-based solvents and materials, are discussed. Comprehensive surveys of ILs for CO2 absorption are presented, which focused mainly on experimental researches, and then the concept is extended to functionalized absorbents and recent developments for CO2 capture. Major advantages and disadvantages of amines-based and ILs-based absorbents are discussed in this review. Solutions of traditional amines (MEA, MDEA, DEA, AMP, PZ, etc.) and ILs (conventional ILs, functionalized ILs, etc.) are summarized. Moreover, research progresses on CO2 separation are also introduced focusing mainly on amines and ILs-based membranes (e.g. supported amines membranes, SILMs). Futhermore, the fixation of CO2 into cyclic carbonates catalyzed by ILs (pure ILs, complex catalyst system with ILs, supported ILs, etc.) is summarized, clearly explaining the mechanism of CO2 fixation with ILs. Finally, exploration of some recent studies about CO2 capture and conversion by ILs and challenges for further progress are presented and related suggestions are put forward.

CO2-responsive switchable emulsions have been of great interest in some industrial processes where the stability of the emulsion is only required temporarily, such as oil transport, drug delivery, and fossil fuel production. The good understanding of the stability and instability mechanism is vital to the switchable behavior between emulsification and demulsification. Herein, a novel approach was developed to determine the interactions between two switchable emulsion droplets directly by a dual-laser optical tweezers instrument. The repulsive force between a couple of tetradecane droplets occurs to increase progressively with the increasing concentration of switchable surfactant in solutions. However, the repulsive force appears to decrease progressively in turn when the switchable surfactant concentration is far higher than the critical micelle concentration (CMC). Moreover, the depletion effect starts to emerge in the higher surfactant concentration which is attributed to the switchable surfactant micelles generated in solutions. In addition, according to the measurements of interaction forces, a mechanism of the switchable behavior is well proposed, which is established by the principle of self-assembly/detachment of the switchable surfactant, resulting in the weakening and re-enhancing of the electrostatic double-layer (EDL) repulsive forces between tetradecane droplets, upon selective introduction and removal of CO2. Based on this work, a novel perspective was provided to study the switchable emulsion, which can contribute instructive messages for the understanding of stability and instability mechanisms of switchable emulsions.

We report here a method for the molecular detection of miRNAs in exosomes and imaging in living cells based on CRISPR–Cas9 and catalytic hairpin assembly. With the cascade signal amplification of catalytic hairpin assembly and high specific recognition of CRISPR–Cas9, the detection method showed a sensitivity of 23.5 fM and was applied for accurate exosomal miR-21 detection and in situ miR-21 imaging.

Imaging-guided diagnosis and chemo-photothermal combination therapy have promising applications for the treatment of cancer. Nevertheless, the accurate diagnosis and efficient treatment of tumors are not yet satisfactory. Herein, a tumor targeting DiR loaded cisplatin-icodextrin prodrug nanoparticle, with selective drug release, was fabricated as a multifunctional theranostic nanoplatform for chemo-photothermal combination therapy. By loading DiR into the hydrophobic domain of folic acid-icodextrin-polycaprolactone (FA-ICO-PCL, FIP) and cisplatin-icodextrin-polycaprolactone (Pt-ICO-PCL, PtIP) co-assembly, the resultant DiR@(PtIP + FIP) (DPtFIP) NPs had a diameter of around 70 nm and showed excellent tumor targeting ability and negligible side effects. Moreover, the DPtFIP NPs achieved real-time NIR fluorescence imaging of solid tumors with high contrast. By the accurate tumor imaging, local laser irradiation dramatically enhanced the chemotherapy for triple-negative breast cancer. Such a biocompatible nanotherapeutic holds great potential for tumor diagnosis and imaging-guided combinational cancer therapy.

Cancer stem cells (CSCs) present grand challenges for triple-negative breast cancer (TNBC). Conventional chemotherapy drugs, including Camptothecin (CPT), not only cannot eradicate CSCs but also foster a suppressive immune microenvironment for the initiation and proliferation of CSCs. Herein, we report a novel prodrug CPT-SS-NLG919 (CN) and its nanoformulation CN@PLA-HES-FA (CN@PHF), which potently suppress CSCs by regulating CSCs niche in murine TNBC 4T1 tumors. Via inducing immunogenic cell death (ICD) and simultaneous inhibiting indoleamine 2, 3-dioxygenase (IDO), CN and CN@PHF promote DC maturation, decrease Treg cells, mitigate tryptophan consumption, and reduce the amount of IL-6, IL-13, and TGF-β, converting CSCs niche to a hostile condition for CSCs to live in and eliminating CSCs efficiently, thereby inducing efficient tumor inhibition in 4T1 tumor models. Our work represents a new paradigm of eliminating CSCs by regulating tumor immune microenvironment and suggests that CN and its nanoformulation CN@PHF are promising candidates for the treatment of intractable TNBC.

More than a 60% increase in crop production is required by the 2050's to feed a growing world population. Understanding how plant functional traits and field management affect crop yields has the potential to improve agricultural productivity, minimize economic and environmental losses, and maximize food security. We explored the influence of winter wheat root characteristics and management on winter wheat growth, yield, and profit using a mechanistic and well-tested ecosystem and crop model, ecosys. We applied and further tested ecosys at an agricultural farm growing winter wheat in Ardmore, Oklahoma, United States. The model accurately predicted observed shoot carbon ((Formula presented.) =0.95), soil moisture ((Formula presented.) =0.67), soil temperature ((Formula presented.) =0.91), and yield (percent error=17%). Numerical optimization experiments were conducted to explore potential improvements of winter wheat yield and profit by modifying root characteristics, including root radius and root:shoot carbon transfer conductance, and fertilizer inputs. Our results show the potential for simultaneously improving winter wheat yields and profits. The optimum conditions were found to be in the range of root radius between 0.1 and 0.3mm, carbon transfer conductance between 0.004 and 0.01 (Formula presented.), and the currently applied fertilizer rate of 112kg (Formula presented.). Under these conditions, improvements in yields and profits of up to approximately 25% and 110%, respectively, were modeled compared to those under baseline root traits. These improvements were achieved by impoverishing root structures, thereby increasing nutrient allocation to grains. Our results also demonstrate and motivate model structures that integrate the complex network of plant physiology, soil nutrient biogeochemistry, hydrology, and management.

Micron-sized aluminum powder exhibits difficulties in ignition and burnout in steam. To overcome these problems, we added various sodium fluoride contents to micron-sized aluminum powder in steam at 800, 900, and 1000 °C to assess their effects on ignition and combustion performances. The ignition delay times, ignition temperatures, and combustion characteristics of all samples were measured primarily using two high-temperature tube resistance electric furnace systems. The experiments showed that adding sodium fluoride to micron-sized aluminum powder decreases its ignition delay time and temperature. Moreover, the ignition delay time and temperature of aluminum powder with addition of sodium fluoride decreases considerably when the temperature increases. For this study, the components and morphology of solid combustion products were obtained using X-ray diffraction and scanning electron microscopy. The combustion efficiency was measured volumetrically using a specially designed apparatus. The obtained combustion efficiency was found to increase with the amount of sodium fluoride added and increase in the temperature. The relationship among the parameters related to combustion characteristics and product characterization was examined in detail to reveal the combustion mechanism.

An alkaline phosphatase-like nanozyme was applied for an immunoassay for the first time. By using nanoceria as the alkaline phosphatase-like catalytic label and CDP-star as the substrate, the chemiluminescent detection of prostate specific antigen was demonstrated. More importantly, the addition of ionic liquid can significantly increase the sensitivity of the immunoassay. With the aid of ionic liquid, an order of magnitude improvement in the sensitivity was achieved with a detection limit of 53 fg mL-1.

MicroRNAs (miRNAs) are noncoding small RNAs that regulate various pathophysiological cellular processes. Here we reported that expression of the miR-378 family was significantly induced by metabolic inflammatory inducers, a high-fructose diet, and inflammatory cytokine TNFa. Hepatic miRNA profiling revealed that expression of miR-378a was highly upregulated which, in turn, targeted the 3’-UTR of PPARa mRNA, impaired mitochondrial fatty acid b-oxidation and induced mitochondrial and ER stress. More importantly, the upregulated miR-378a can directly bind to and activate the dsRNA-dependent protein kinase R (PKR) to sustain the metabolic stress. In vivo, genetic depletion of miR-378a prevented PKR activation, ameliorated inflammatory stress and insulin resistance. Counterbalancing the upregulated miR-378a using nanoparticles encapsulated with an anti-miR-378a oligonucleotide restored PPARa activity, inhibited PKR activation and ER stress, and improved insulin sensitivity in the fructose-fed mice. Conclusion: Our study delineated a novel mechanism of miRNA-378a in the pathogenesis of metabolic inflammation and insulin resistance through targeting metabolic signaling at both mRNA (e.g., PPARa) and protein (e.g., PKR) molecules. This novel finding of functional interaction between miRNAs (e.g., miR-378a) and cellular RNA binding protein(s) (e.g., PKR) is biologically significant as it greatly broadens the potential targets of miRNAs in cellular pathophysiological processes.

Hydrothermal pretreatment (HT) is an effective method to upgrade biochar pellets, while little attention is paid to wood vinegar (WV), the byproduct of biochar pellets production. Therefore, Chinese fir sawdust (FS) and cotton stalk (CS) were hydrothermally pretreated first at 180–280 °C and then pyrolyzed at 350 °C in the study. The effect of hydrothermal pretreatment on the properties of biomass was evaluated by the Van Soest method and thermogravimetric method. The yield, pH, density, and composition of WV were analyzed. The results showed that hemicellulose and cellulose were completely decomposed at HT temperatures of 230 °C and 280 °C respectively. The removal of hemicellulose and the enrichment of cellulose and lignin in the samples pretreated before 230 °C result in a higher density and lower pH of WV, while the yield only increases before 200 °C. Compared with CS samples, the higher content and reactivity of cellulose, especially amorphous cellulose, and lignin in FS samples results in the higher yield of the organic compounds in FSWV. With HT temperature increasing to 230 °C, the content and yield of acids in FSWV/CSWV shows a declining trend, and the content and yield of phenols, ketones, and aldehydes increase. HT pretreatment below 230 °C can upgrade WV.

Telomerase is a promising biomarker and a potential therapeutic target of malignant tumors. Reliable, facile, and sensitive telomerase activity analysis is of vital importance for both early diagnosis and therapy of malignant tumors. Herein, we proposed a novel fluorescent assay termed catalytic hairpin assembly-assisted rolling circle amplification (CAR) for both in vitro and in situ high-sensitive telomerase activity detection. In the presence of active telomerase, the extension of a designed telomerase primer was limited to five bases (GGGTT), thus forming short telomerase products. Afterward, the obtained telomerase extension products cyclized Padlock and subsequently initiated the rolling circle amplification (RCA). In order to maintain a higher sensitivity, an ingeniously designed catalytic hairpin assembly (CHA) was attached for both signal amplification and result readout. The highlights of the CAR method were concluded as follows: (i) dual signal amplification from CHA and RCA ensures high sensitivity and (ii) the CAR method has the potential for both in vitro and intracellular imaging of telomerase activity. We believe that the CAR method would be of great potential for the diagnosis and therapy of various human diseases.

SUMMARY Induced calcite precipitation is used in geotechnics to modify the mechanical and hydrological properties of the underground. Laboratory experiments have shown that spectral induced polarization (SIP) measurements can detect calcite precipitation. However, the results of previous studies investigating the SIP response of calcite precipitation were not fully consistent. This study aims to investigate how the SIP response of calcite depends on solute concentration to explain the differences in SIP response observed in previous studies. A four-phase experiment with SIP measurements on a column filled with sand was performed. In phase I, calcite precipitation was generated for a period of 12 d by co-injecting Na2CO3 and CaCl2 solutions through two different ports. This resulted in a well-defined calcite precipitation front, which was associated with an increase in the imaginary part of the conductivity ($\sigma ^{\prime\prime}$). In phase II, diluted solutions were injected into the column. This resulted in a clear decrease in $\sigma ^{\prime\prime}$. In phase III, the injection of the two solutions was stopped while calcite precipitation continued and solute concentrations in the mixing zone decreased. Again, this decreased $\sigma ^{\prime\prime}$. Finally, the injection rate of the Na2CO3 solution was reduced relative to that of the CaCl2 solution in phase IV. This resulted in a shift of the mixing zone away from the calcite precipitation front established in phase I and an associated decrease of $\sigma ^{\prime\prime}$. These results imply that the SIP response of calcite is highly sensitive to the solute concentration near the precipitates, which may explain previously reported conflicting results.

Alkene epoxidation, which consists an important reaction in the synthesis of various fundamental chemical compounds, has aroused increasing attention in the field of organic synthesis. Hydrogen peroxide that is often considered as a green oxidant for the epoxidation of olefins is relatively unstable when reacting in batch reactor. Microreactor system possesses the advantages of high mass and heat transfer performances as well as great controllability, making it a suitable pathway for the epoxidation of olefins. In this work, a highly efficient microreaction system for epoxidation of styrene is studied. Both high conversion of styrene and excellent product selectivity could be achieved. The effects of temperature, residence time, molar fraction of catalyst, molar ratio of MeCN/t-BuOH, flow rate of H2O2 and buffer solution were studied. According to the experiment data, kinetic equation was built, which will be in favor of verifying the rationality of the reaction mechanism and optimizing experimental conditions.

Hydrogen-enriched natural gas is a promising low-carbon fuel in combustion devices. To better assess its feasibility from the extinction prevention point of view, the extinction of near-limit premixed hydrogen-methane/air flames over a wide range of equivalence ratios was measured using the single-flame counterflow configuration. Results showed that the hydrogen addition resulted in a greater extinction stretch rate. Further analysis demonstrated that the extinction stretch rate of premixed hydrogen-methane/air flames linearly correlated with the corresponding reference flame speed. Thereby a combustion regime map diagram, separating the burning and extinction, was sketched. In addition, critical extinction Damkӧhlor number of premixed hydrogen-methane/air flames was investigated and it was found to be insensitive to the hydrogen addition and equivalence ratio. Finally, the hydrogen addition effect and the corresponding extinction response were assessed for two scenarios, 1) constant thermal load (gas turbine, gas-fired boilers, etc.), and 2) constant fuel injection pressure (gas stove, oven, etc.). The results indicated that H2 addition promoted the combustion safety by increasing the extinction stretch rates, but an allowable H2 variation window existed when considering the unexpected high-temperature damage of the burners. The allowable H2 variation window of Scenario 1 was found much broader than that of Scenario 2.

Antimicrobial peptides (AMP) secreted by the granular glands of frog skin have been widely reported to exhibit strong bacteriostatic and bactericidal activities. Many of them have been documented with potent antiproliferative effects on multiple cancer cells, many studies also suggested that AMPs exert their functions via disrupting cell membranes. However, whether and how other cell death induction mechanism is involved in mammalian cancer cells has rarely been investigated. In this study, a novel AMP named Dermaseptin‐PS1 was isolated and identified from Phyllomedusa sauvagei, it showed strong antimicrobial activities against three types of microorganisms. In vitro antiproliferative studies on human glioblastoma U‐251 MG cells indicated that Dermaseptin‐PS1 disrupted cell membranes at the concentrations of 10−5 M and above, while the cell membrane integrity was not affected when concentrations were decreased to 10−6 M or lower. Further examinations revealed that, at the relatively low concentration (10−6 M), Dermaseptin‐PS1 induced apoptosis through mitochondrial‐related signal pathway in U‐251 MG cells. Thus, for the first time, we report a novel frog skin derived AMP with anticancer property by distinct mechanisms, which largely depends on its concentration. Together, our study provides new insights into the mechanism‐illustrated drug design and the optimisation of dose control for cancer treatment in clinic.

Microbial sulfate reduction occurs ubiquitously in natural environments. In oil and gas reservoirs, the generation of sulfide (also known as souring) can result in the corrosion of steel infrastructure and downgrading of oil quality, among other environmental and health-related concerns. The complex interplay between hydrological, geochemical, and biological processes during souring is poorly understood, preventing effective treatment and mitigation especially in naturally heterogeneous subsurfaces. In this work, three-dimensional flow tank experiments are utilized as a mesoscale experiment that links well-constrained batch and column experiments to field measurements. The mesoscale tank experiment investigating perchlorate treatment of souring is coupled with reactive transport modeling to understand the effects of heterogeneity on souring and effectiveness of perchlorate treatment. Tracer experiments were conducted at the start and end of the experiment to constrain flow pathways and heterogeneities. Is...

The effects of CO2 and H2O addition on benzene and PAH formation in a laminar premixed CH4/O2/Ar flame at atmospheric pressure were numerically investigated using two recently developed kinetic mec...

This study investigated the impact of in situ exopolysaccharides (EPS) on the properties of dough and quality of Chinese steamed bread (CSB). Sourdoughs were fermented with dextran-producing Weissella confusa QS813, with and without sucrose addition at 20 °C and 35 °C, respectively. The highest EPS content and lowest titratable acidity value were obtained in sucrose-enriched sourdough fermented at 20 °C (WS20+). Addition of WS20 + significantly improved proofing performance and induced glutenin macropolymer (GMP) particle agglomeration of dough. Microstructure results revealed a more continuous, connected network in WS20 + dough and better crumb structure in the corresponding CSB. The quality of CSB was enhanced upon addition of WS20+. Low EPS yield in sourdough without sucrose negatively affected dough and CSB quality. Increased acidification in sucrose-enriched sourdough fermented at 35 °C masked the beneficial effects of EPS. Therefore, both high EPS generation and mild acidification contributed to the beneficial effect of W. confusa sourdough on CSB quality.

Bio-inspired polydopamine (PDA) based nanomaterials, particularly nanoparticles (NPs), received tremendous attention and have been applied to various fields, including drug delivery. Nonetheless, bare PDA NPs will aggregate in physiological conditions and can be hardly applied for in vivo explorations. Herein, we present the preparation of novel hydroxyethyl starch coated PDA (HES-PDA) NPs for cancer chemotherapy. The frequently used PEG-modified PDA (PEG-PDA) NPs are also manufactured as a control and doxorubicin (DOX) is chosen as a model drug. The stability, drug loading capacity, lyophilization and rehydration property, biodistribution, in vitro and in vivo anti-tumor efficacy, and toxicity of DOX-loaded HES-PDA (DOX@HES-PDA NPs) are investigated. Collectively, DOX@HES-PDA NPs, similar to DOX@PEG-PDA NPs, show potent antitumor efficacy and dramatically mitigate toxicity associated with DOX. The HES-PDA NPs reported herein represent a novel biodegradable multifunctional nano-drug formulation, with significant translation potentials, for cancer chemotherapy against a wide spectrum of cancers.

Dysregulation of hepatic glucose production (HGP) serves as a major underlying mechanism for the pathogenesis of type 2 diabetes mellitus (T2D). The pancreatic hormone glucagon increases, and insulin suppresses HGP, controlling blood glucose homeostasis. The forkhead transcription factor Foxo1 promotes HGP through increasing expression of genes encoding the rate-limiting enzymes responsible for gluconeogenesis. We previously established that insulin suppresses Foxo1 by Akt-mediated phosphorylation of Foxo1 at Ser256 in human hepatocytes. In this study, we found a novel Foxo1 regulatory mechanism by glucagon, which promotes Foxo1 nuclear translocation and stability via cAMP- and protein kinase A (PKA)-dependent phosphorylation of Foxo1 at Ser276. Replacing Foxo1-S276 with alanine (A) or aspartate (D) to block or mimic phosphorylation, respectively, markedly regulates Foxo1 stability and nuclear localization in human hepatocytes. To establish in vivo function of Foxo1-Ser276 phosphorylation in glucose metabolism, we generated Foxo1-S273A and Foxo1-S273D knock-in (KI) mice. The KI mice displayed impaired blood glucose homeostasis, as well as the basal and glucagon-mediated HGP in hepatocytes. Thus, Foxo1-Ser276 is a new target site identified in control of Foxo1 bioactivity and associated metabolic diseases.

Organic solvents play a vital and irreplaceable role in multiple modern industries, research laboratories, and daily routines, especially in chemical and pharmaceutical industries, as they serve as reaction media, and they are also used in separation and purification of synthetic products and for cleaning equipment. A large number of organic solvents are considered as hazardous compounds, which can cause either environmental or health issues. Both advantages and disadvantages call for facile and accurate detection of organic solvents. Herein, we integrated an ultrathin stimuli-responsive copolymer layer into an Au–polymer–Au “sandwich-structure”, termed etalon, and realized fast and visual identification of four commonly used typical organic solvents, namely, ethanol (alcohol), acetone (ketone), tetrahydrofuran (ethers), and dimethylformamide (amide). The results indicated that substantial changes (over 300 nm) of spectral peaks or troughs were induced by immersing the sensor into different solvents. Distinguishable structural colours enabled differentiation of hazardous organic solvents by the naked eye. The original optical property of the sensor was consistent with theoretical simulation data of the FDTD software. To optimize responsive optical signals, the fabrication parameters such as Au layer thickness, polymer compositions, and UV cross-linking time were modulated. The sensors exhibited high stability and reproducibility, and the method was not limited by the composition of substrates. Repetition of the sensor was also tested, and the performance did not decline after 25 cycles. Furthermore, through UV exposure under masks, the sensor could display patterns clearly and rapidly after being immersed in organic solvents.

To improve the ignition and combustion characteristics of micrometer-sized aluminum powder in steam at 900 °C, the present study focuses on the effects of adding different contents of Mg, NaF, and NaBH4. Experiments were conducted in two high-temperature tubular resistance furnaces to measure ignition temperatures, maximum combustion temperatures, and ignition delay times and to understand the combustion features of all samples. The experimental results show that Mg addition results in a reduced ignition temperature and ignition delay time of the micrometer-sized aluminum powder and causes two burning stages (a double-peak feature) because the Mg powder preferentially ignites before the micrometer-sized aluminum powder. The maximum combustion temperature increases with increasing Mg content. The ignition temperature and the ignition delay time are also significantly decreased with increased NaF or NaBH4 addition. However, the addition of NaF or NaBH4 lowers the maximum combustion temperature. The morpholo...

Various damages, including corrosion, fouling, and blue plumes, can be caused by sulfur trioxide (SO3) in the flue gas of a coal-fired boiler on boiler equipment and the atmospheric environment. The increasing demand for energy conservation and emission reduction requires accurate knowledge on predicting and controlling the SO3 concentration. Accurate knowledge on the effect of the factors that influence SO3 in flue gas is necessary as well. Therefore, in this study, various SO3 concentrations under different flue gas conditions are measured with measuring devices built based on controlled condensation and S balance methods. To further study the effect of the factors that influence SO3 in flue gas, an improved SO2/O2/H2O/CO2/CO/NO kinetic mechanism is built based on previously developed mechanisms and validated with previous experimental data. SO3 concentrations under the established flue gas conditions and with increasing residence time are numerically calculated. The SO3 concentration in flue gas is mai...

Summary Water displacement method is used to study the influence of temperatures (60–80°C), additives (Na2CO3, NaCl, Na2CO3/NaCl) and concentrations on the reaction characteristics and kinetics of Al–H2O. Results show that the reaction rate and the hydrogen yield are enhanced with the increase of the temperature or by adding Na2CO3. The reaction rate is decreased by adding NaCl, but which has less effect on the hydrogen yield. For the mixture additive, Na2CO3 plays a key role in improving the hydrogen yield and the reaction rate. The influence degree of different factors is analyzed by orthogonal method. The most obvious factor is additive, but additive concentration has a minimum influence. The solid products are collected and analyzed by X-ray diffraction and transmission electron microscopy. Al, Al(OH)3 and AlO(OH) are detected. The spherical particles are obviously found at the initial reaction stage. However, they change to flocs at the end of reaction. Kinetic analysis shows that the reaction mechanism of Al–H2O is changed by adding Na2CO3 or mixture, but it is not affected by adding NaCl. Moreover, the apparent activation energy of Al–H2O is 74.49 kJ mol−1, while it is only 43.03 kJ mol−1 for Al–H2O with 5 wt% Na2CO3 addition. Copyright © 2017 John Wiley & Sons, Ltd.

The distributions of soot volume fraction, soot number density, and soot particle size in a coal-air turbulent jet flame was numerically investigated using a soot formation model developed in our previous study. In addition, the effect of radiation from different radiative media on the flame temperature was assessed and discussed. Validated by the reported experimental measurements, the distribution of soot volume fraction in the turbulent air-coal jet flame was well predicted. It was also found that soot particles were formed and accumulated in the high temperature zone with remarkable oxygen deficient. In the same time, the temperature of the coal-air jet flame was reduced remarkably by soot radiation but barely by soot formation. For the simulated flame, at a downstream location of 200 mm from the jet exit, the heat loss caused by the thermal radiation of coal particles, soot particles and gas species resulted in a temperature decrease of 262 K, 238 K and 102 K respectively. Different radiative media induced remarkably different distributions of absorption coefficient, and the emitting heat loss from the media was determined by the local absorption coefficient and temperature.

Visible detection of electromagnetic waves is important. Herein, we propose a method to trace invisible near infrared (NIR) light by combining thermo-sensitive one-dimensional photonic crystals (1DPCs) and Au nanorods (NRs). Au NRs first absorb the NIR light and convert it into heat energy, then the temperature increase and the thermo-sensitive 1DPC produces a response through conformation transfer of the PNIPAm layer leading to the disappearance of its structural color, which is a quite obvious signal. We also realize the differentiation of NIR light belonging to a different wavelength range by building hybrid 1DPCs with Au NRs of different absorbance. The 1DPC/Au hybrid system is easy to prepare in a large area with low cost, the signal read-out can be observed by the naked eye and the polymer matrix also makes it a promising flexible device. We believe that such a device will be portable and has the potential to be used in various applications in daily life.

A transient mathematical model was developed to describe soot formation during the combustion of single coal particles based on the static semi-empirical model presented by Fletcher and coworkers. Sensitivity analyses of the model parameters show that soot emissivity and mass diffusivity of tar play an important role in predicting soot volume fraction ( f v ) and flame temperature ( T f ). The model was applied to simulate the combustion of single bituminous coal particles with initial diameter (2 r 0 ) of 83 µm in a drop tube furnace and air atmosphere. It was found that soot is only formed within the first ∼ 5 ms after the appearance of the volatile flame. Although most of the soot is oxidized during the volatile flame phase, a small portion of soot still remains during the char combustion. Due to the soot presence, the volatile flame duration is extended by 2.6 ms. Compared with the soot-free flame, the sooting flame has remarkable lower T f and its peak T f value is ∼ 410 K lower. As a consequence, char combustion starts at a temperature that is ∼ 125 K lower than that of the soot-free case. Spatially, the peak f v at 16.6 ms appears at 4.5 r 0 and soot oxidation zone spans to ∼ 10 r 0 . The model was validated by comparing the predicted T f and f v under different O 2 mole fractions ( x O2 ) with recent experimental results reported by Khatami and coworkers. The predicted trends are consistent with those of the experimental results. With increasing x O2 , T f increases, but the increase rate becomes more gradual at a large x O2 . While for f v , a non-monotonic variation is observed, where soot first increases and then decreases with a peak value occurring at x O2 ≈ 40%.

To develop the combustion characteristics of aluminum powder in steam, the ignition and combustion process of aluminum powder with different additives (KBH4, ammonium perchlorate (AP) and NaCl) addition at different levels were studied using a transparent pipe furnace. The temperature variation of these samples was measured using a thermocouple, and a high-speed camera was used to record combustion phenomenon. The solid combustion products of these samples with good characteristics were collected to analyze the microstructure and component. The results indicate that the ignition temperature of aluminum powder is decreased by adding these additives or increasing the content of the additive, whereas the maximum combustion temperature is different. When adding 3 wt% KBH4, the maximum combustion temperature reaches up to 1404 °C, which is higher than that of the original aluminum powder. However, upon addition of AP or NaCl the maximum combustion temperature decreases. Simultaneously, the combustion flame of aluminum powder with addition of KBH4 or AP is comparatively intense and bright, whereas the addition of NaCl reduces combustion intensity. The different influence mechanisms of additives on the ignition and combustion of aluminum powder are believed to be responsible for the experimental results.

Constructing a tumor microenvironment stimuli activatable theranostic nanoparticle with simple components and preparation procedures for multimodality imaging and therapy remains a major challenge for current theranostic systems. Here we report a novel and simple glutathione (GSH)-responsive turn-on theranostic nanoparticle for dual-modal imaging and combination therapy. The theranostic nanoparticle, DHP, consisting of a disulfide-bond-linked hydroxyethyl starch paclitaxel conjugate (HES-SS-PTX) and a near-infrared (NIR) cyanine fluorophore DiR, is prepared with a simple one-step dialysis method. As DiR is encapsulated within the hydrophobic core formed by HES-SS-PTX, the fluorescence of DiR is quenched by the aggregation-caused quenching (ACQ) effect. Nonetheless, once DHP is internalized by cancer cells, the disulfide bond of HES-SS-PTX can be cleaved by intracellular GSH, leading to the synchronized release of conjugated PTX and loaded DiR. The released PTX could exert its therapeutic effect, while DiR could adsorb onto nearby endosome/lysosome membranes and regain its fluorescence. Thus, DHP could monitor the release and therapeutic effect of PTX through the fluorescence recovery of DiR. Remarkably, DHP can also be used as an in vivo probe for both fluorescent and photoacoustic imaging and at the same time achieves potent antitumor efficacy through chemo-photothermal combination therapy. This study provides novel insights into designing clinically translatable turn-on theranostic systems.

Deep understanding of nucleate boiling heat transfer mechanism of saline solution is of great importance for the design and safe operation of steam generation equipment. In this paper, the nucleate flow boiling process of saline solution in a vertical heated pipe was experimentally studied within the concentration range of 0 % ∼ 6 %. In order to realize the visualization, the vertical heated pipe was made of transparent silica glass and a transparent ITO heater was used to provide energy for boiling. The high-speed high-resolution camera was used to capture the vapor-liquid two-phase flow structure. The bubble behaviors such as bubble departure diameter, bubble departure frequency, bubble growth time and waiting time were investigated under different operating conditions. The experimental results showed that the heat transfer deterioration did not occur within the solution concentration of 6% in this work. Under some low heat flux conditions, the heat transfer coefficients of solution can be higher than those of pure water. The reason for this phenomenon can be explained by the different bubble behaviors. Comparing to pure water, the bubble departure diameter of saline solution is bigger and bubble departure frequency is lower. The influences of operating parameters, including concentration, mass flux (200 kg/m2s ∼ 600 kg/m2s), heat flux (30 kW/m2 ∼ 180 kW/m2) and subcooling of fluid (5 K ∼ 35 K), on the nucleate boiling heat transfer coefficients and bubble parameters were comprehensively studied.

Photodynamic therapy (PDT) is a clinically approved cancer treatment which utilizes reactive oxygen species (ROS) to eradicate cancer cells. But the high concentration of GSH inside tumor cells can neutralize the generated ROS during PDT, resulting in an insufficient therapeutic effect. To address this issue, we combined ICG-loaded nanoparticles with PEITC for potent PDT. ICG encapsulated in novel hydroxyethyl starch-oleic acid conjugate (HES-OA) nanoparticles (∼50 nm) exhibited excellent stability and efficient singlet oxygen generation under laser irradiation, promoted cellular uptake, and enhanced tumor accumulation, whilst PEITC depleted intracellular GSH significantly. As a result, PDT based on ICG-loaded NPs combined with PEITC synergistically suppressed cancer cells both in vitro and in vivo. Potentiating ICG-loaded NPs with PEITC represents a novel and efficient strategy to enhance PDT efficacy.

Tumor penetration is the bottleneck for current cancer nanomedicine, limiting the ultimate antitumor efficacy in the clinic. Herein, by exploiting the well-known instability of indocyanine green (ICG), we report the preparation of near infrared (NIR) light responsive nanoparticles (NP) for enhanced tumor penetration. ICG crosslinks hydroxyethyl starch (HES) and doxorubicin (DOX) conjugates (HES-SS-DOX) via noncovalent interactions, facilitating the formation of ICG@HES-SS-DOX NP. The light triggered degradation of ICG leads to the dissociation of such NP, and the resulting HES-SS-DOX has been shown to penetrate deeper in both H22 tumor spheroids and tumor bearing mice, due to the photothermal effect of ICG. Therefore, the disintegrable ICG@HES-SS-DOX NP have better tumor penetration capacity than their counterparts, which originally cannot dissociate under NIR light stimulation. The reported ICG@HES-SS-DOX NP might be potent in treating malignant tumors with dense extracellular matrices, such as liver and pancreatic cancers. This study opens up a novel functionality of FDA-approved ICG for cancer nanotherapeutics.

Hydrogen generation from rapid hydrolysis of aluminum in sodium fluoride solution was investigated through a hydrolysis experiment. Rapid and instant hydrogen yield were observed using sodium fluoride as additive. The experimental results demonstrate that the increase of temperature and the amount of additives in a certain range will boost the hydrogen production. The amount of additives outside the range only has an effect on the rapid hydrolysis of the aluminum during the initial stage, but the total amount of hydrogen produced doesn’t increased significantly. Theoretical analysis of the effects of the mixing ratio and the temperature on the hydrogen production rates were performed using the shrinking core model and the kinetic model. The shrinking core model parameter a and k indicate the film change degree of porosity and thickness and the effect of time on the diffusion coefficient. the kinetic model is verified and the activation energy confirming hydrogen yield control by a molecular diffusion process. Correspondingly, mechanisms of Al corrosion in NaF solutions under low and high alkalinity were proposed, respectively.

Considered as an important C1 source on earth, carbon dioxide (CO2) utilization and fixation has aroused great attention. Synthesis of cyclic carbonate are one of the most widely industrialized routes. Ionic liquids have been studied for highly efficient cyclic carbonate production due to their distinguished characteristics. In this work, highly efficient synthesis of propylene carbonate catalyzed by [bmim]Br was achieved via a continuous-flow microreaction system. Based on that, influence factors and kinetics parameters for propylene carbonate synthesis were obtained. And the flow patterns were investigated via transparent tube, which were proved to be slug flow. The activation energy for [bmim]Br in this microreaction system was 57.4 kJ/mol with the temperature range from 110 to 140 ℃, and the reaction was found to follow first-order on PO and CO2 concentrations, and first-order on [bmim]Br concentration. Verification of the kinetic models was also studied and proved a less than 12 % error range.

Oxygen-enriched circulating fluidized bed (CFB) technology is considered as one of the low carbon emission power generation technologies. By recycling the flue gas into the furnace, the CO2 concentration in the exhaust gas can reach over 90%. The coal ignition temperature and ignition characteristics are important factors for boiler design and for choosing the feeding temperature during the transition from air-firing to oxy-firing. The ignition and combustion processes of five types of coal under four different atmospheres (air, O2 27%, O2 40%, O2 53%) were measured in a laboratory scale fluidized bed reactor (FBR) with an under-bed preheat system. Using thermocouples and a gas analyzer, the changes in bed temperature and the concentrations of different components, such as O2, CO2 and CO, in flue gas were directly measured to determine the coal ignition temperature, TiF. It was found that TiF decreases with increasing O2 concentration. At lower bed temperatures, two-stage ignition processes were observed in certain ranges of initial bed temperature and oxygen concentration. The influence of initial bed temperature on volatile release and the SO2 emission in the ignition processes were also discussed.

Zhundong coal is one of the most important coals in China due to its huge reserve, but it causes severe fouling and slagging problems when it is burnt in boilers for its high AAEMs (alkali and alkaline earth metal species) contents. Accurately determination of the occurrence modes and contents of AAEMs in Zhundong coals is a necessary step to overcome the ash-related problems. Nowadays, different researchers used different methods or procedures to determine AAEMs in Zhundong coals, and the data were scattering. Based on a series of experiments on the effects of extraction conditions, an improved extraction method with clearly defined conditions for each extraction step was proposed. 0.1 mol/L NH 4 Cl (pH = 8.5) instead of 1 mol/L NH 4 OAc (pH = 7) was used to extract the exchangeable AAEMs in Zhundong coals to avoid the high solubility of carbonates in the extraction solution. The improved method was more accurate and took much less time than the conventional one. With the proposed extraction method, the occurrence modes and contents of AAEMs in three Zhundong coals were measured. The results revealed that Na is mainly water soluble (Na w /Na total = 50–85%) which is halite or in the form of surface bound Na + , while Ca and Mg are mainly acid soluble (Ca ac /Ca total = 60–90%, Mg ac /Mg total = 45–90%) which are carbonates together with a little amount of sulfates. Exchangeable AAEMs organically bonded to the coal matrix are not the main occurrence mode of AAEMs. Acid insoluble Ca-species could be rankinite. The amounts of AAEMs in the same occurrence mode could be remarkably different among coals from different Zhundong district. The improved sequential extraction method can be extended to determine AAEMs in high carbonate-containing coals.