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In grape, high temperatures and low humidity prolong midday depression of foliar photosynthesis and dramatically reduce fruit yield. In this study, we explored the effects of various mist micro-spray treatments on grape photosynthesis at a test site in Shanshan County (N, 42.91°; E, 90.30°), Turpan, Xinjiang, China. We tested four different mist micro-spray durations including 1 h (WP1), 2 h (WP2), 3 h (WP3), and 0 h (CK). WP1, WP2, and WP3 affected canopy air temperature and humidity for 5 h, 7 h, and 9 h, respectively. At 12:30, WP1, WP2, and WP3 had the strongest cooling effect and altered temperature by −5.12 °C, −5.09 °C, and −5.17 °C respectively. The relative chlorophyll content was higher in the upper than the lower canopy leaves. There were no differences in the same leaf layers across treatments. The net photosynthesis and transpiration rates and stomatal conductance were higher for the upper than the lower canopy leaves. Compared with CK, the mist micro-spray treatments mitigated “midday depression” in the upper leaves and eliminated it altogether in the lower leaves. Mist micro-spray for 1 h d-1 most effectively improved grape leaf photosynthesis. The findings of the present study lay an empirical foundation for improving grape leaf photosynthesis and fruit yield.

Antibiotic fermentation residue (AFR) is a form of bioavailable matter, that represents a typical category of hazardous waste associated with drug production in China. The disposal of these residues seriously restricts the sustainable development of the pharmaceutical industry. In this study, the steam explosion and aerobic composting (SEA-CBS) system was developed to thoroughly convert neomycin fermentation residue to organic fertilizer. The results implied that the ultimate removal rate of antibiotics was as high as 99.9% in all cases, including macrolide (kitasamycin and spiramycin), lincosamide (lincomycin), and beta-lactam (cephalosporin and penicillin) antibiotic biowastes. Pot experiments were also conducted to study the attenuation rule of antibiotic residues in the soil, and the distribution of antibiotic resistant genes from trace antibiotics. The produced fertilizer presented the better performance on mustard growth than conventional fertilizers. The average plant height and biomass were increased by 14.33%–55.83% and 136.71%–326.83%, respectively, after SEA-CBS pretreatment. Moreover, neomycin was the primary selective pressure, and six antibiotic resistance genes (ARGs) correlated with neomycin were screened. The acc(6′)ib gene was identified as the target ARGs, the main resistance mechanism was antibiotic inactivation, and the absolute and relative abundances were 1.06 × 105 ± 3.80 × 104 copies/g and 6.23 × 10−4 ± 1.75 × 10−4 copies/16 s in the NFR-amended soils. The microbial community analysis showed that the variation of the soil microbial community was not dominated by neomycin fermentation residue (NFR) at initial concentrations below 0.42 μg/kg soil. This work demonstrated that the SEA-CBS system not only functioned as an efficient technology for concurrent neomycin sulfate removal and NFR composting, but also applied to a wide range of other antibiotic bio-wastes, which may benefit the recycling of AFR, as well as the data provide a theoretical basis for future agricultural utilization and safe evaluation.

A fully degradable PLA/starch composite was prepared by one-step in-situ compatibilization method. The effects of raw materials ratio and maleic anhydride （MAH） dosage were studied by thermogravimetric analyzer (TG) and scanning electron microscopy (SEM). The thermal stability and microstructure of the composites were investigated, and the non-isothermal thermal decomposition kinetics of the composites were discussed. The DTG results show that there are two distinct maximum decomposition rate peaks in the unmodified composites. After the MAH is added, the maximum decomposition rate peaks of the composites are close to each other. In addition, as the MAH dosage increases, the maximum rate of decomposition peak gradually shifts to a lower temperature. The SEM results show that the compatibility of the composites is improved after the addition of MAH. And both the Kissinger and Flynn-Wall-Ozawa methods are well described for the non-isothermal thermal decomposition kinetics of PLA and PLA/starch composites.

Nylon 6 (PA6) grafted onto carbon fiber (CF) after chemical oxidation treatment was in an attempt to reinforce the mechanical properties of carbon fiber composites. Scanning electronic microscopy (SEM), Fourier transform infrared analysis (FT-IR), X-ray photoelectron spectroscope (XPS) and thermogravimetric analysis (TG) were selected to characterize carbon fibers with different surface treated. Experimental results showed that PA6 was grafted uniformly on the fiber surface through the anionic polymerization. A large number of functional groups were introduced to the fiber surface and the surface roughness was increased. After grafting PA6 on the oxidized carbon fibers, it played an important role on improving the interfacial adhesion between the fibers and the matrix by improving PA12 wettability, increasing chemical bonding and mechanical interlocking. Compared with the desized CF composites, the tensile strength of PA6-CF/PA12 composites was increased by 30.8% from 53.9 MPa to 70.2 MPa. All results indicated that grafting PA6 onto carbon fiber surface was an effective method to enhance the mechanical strength of carbon fiber/nylon 12 composites.

Metal-organic frameworks (MOFs) have attracted numerous attentions as anode materials for lithium-ion batteries (LIBs) owing to their unique tunable structures. However, utilizing MOFs in electrochemical devices has been hampered by the inferior electrical conductivity and poor stability that dominate the cycling stability and rate performance of electrodes. Herein, a Ni-PTA/graphene hybrid with porous spherical structure has been successfully constructed by interconnected needle-like Ni-MOFs nanocrystals after the introduction of amine functionalized graphene (NG). The conductivity and structural stability of the composites have been greatly improved due to the chemical bonds formed between the N-containing graphene and the MOFs. When used as anode materials for LIBs, the synthesized Ni-PTA/NG composite shows a superior Li storage with a reversible capacity of 1585 mAh g−1 at a current density of 200 mA g−1. In addition, Ni-PTA/NG composite demonstrates an ameliorative rate performance (340 mAh g−1 at 5 A g−1) and long-term cyclability (570 mAh g−1 at 1 A g−1 after 420 repeated cycles), significantly higher than traditional graphene/MOF composite materials. The novel method in this work paves a new way to form 3D structure by using NG to induce MOF germination, which may be extended to preparing other metal/metal oxides materials for electrochemical energy-storage systems.

As anode materials for lithium-ion batteries, SiO2 is of great interest because of its high capacity, low cost and environmental affinity. A facile approach has been developed to fabricate SiO2@C hollow spheres by hydrolysis of tetraethyl orthosilicate (TEOS) to form SiO2 shells on organic sphere templates followed by calcinations in air to remove the templates, and then the SiO2 shells are covered by carbon layers. Electron microscopy investigations confirm hollow structure of the SiO2@C. The SiO2@C hollow spheres with different SiO2 contents display gradual increase in specific capacity with discharge/charge cycling, among which the SiO2@C with SiO2 content of 67 wt% exhibits discharge/charge capacities of 653.4/649.6 mA h g−1 over 160 cycles at current density of 0.11 mA cm−2. The impedance fitting of the electrochemical impedance spectroscopy shows that the SiO2@C with SiO2 content of 67 wt% has the lowest charge transfer resistance, which indicates that the SiO2@C hollow spheres is promising anode candidate for lithium-ion batteries.

This work aims to study the surface modification and reinforcing effect in carbon fiber (CF)/nylon 12 (PA12) composites of CFs, and more importantly, resolves the practical application problems of modified CF/PA12 composite powder in selective laser sintering (SLS). CFs were surface modified by nitric acid (HNO3), the surface changes of CFs were characterized by SEM, FT-IR and XPS. Initially, the effects of the experimental factors on the properties of composites were investigated, and the CF/PA12 composite powder prepared with optimized technological parameters was subsequently adopted in SLS experiments. The sintering behavior and relationship between mechanical properties and porosity of sintered specimens were also discussed. The results indicated that the oxygen functional groups on HNO3 modified CFs were partly thermally decomposed and released as gas in the process of laser sintering, which caused high porosity and poor mechanical properties of sintered specimens. Treating CFs at 400 °C (approximately the laser sintering temperature) after HNO3 modification was proposed as a solution. This treatment preserved part of the modified effect and reduced the porosity of the composites at the same time. Compared with the unmodified CF/PA12 sintered specimens, the tensile strength, tensile modulus, flexural strength, and flexural modulus were all increased to different degrees. Keywords: Carbon fiber, Surface modification, Modified carbon fiber/nylon 12 composite powder, Selective laser sintering, Porosity

Zn/Mg/Al layered double hydroxide (Zn/Mg/Al-LDH) was prepared by co-precipitation method. The structure of Zn/Mg/Al-LDH was characterized by XRD. The results show that the samples have typical hydrotalcite structure. They were used as adsorbents to remove phosphorus from wastewater. The effects of pH value, phosphorus concentration, adsorbent dosage, oscillation intensity and reaction time on phosphorus adsorption capacity were investigated by single factor control variable method. The results show that the adsorption equilibrium of Zn/Mg/Al-LDH can be reached after 24 h. The optimal experimental conditions are as follows: stirring rate is 180 R/min, pH value is 6, and reaction temperature is 50 °C. Under above conditions, when the initial phosphorus concentration is 50mg/L, the adsorption capacity of Zn/Mg/Al-LDH for phosphorus is 54.10mg/g when the adsorption equilibrium is reached. When the initial phosphorus concentration is 200mg/L, the adsorption capacity is 69.70mg/g, and the saturated adsorption capacity is 70.37mg/g. In the simulated practical engineering application, when the discharged phosphorus meets the standard, the phosphorus adsorption capacity of Zn/Mg/Al-LDH is 37.09mg/g, and the phosphorus removal rate is as high as 99.76%.

Plant fiber has a complex aggregated structure, high crystallinity and a large number of hydrogen bonds, and has low chemical reaction activity. Therefore, in order to improve the reactivity, the plant fiber needs to be pretreated before chemical modification. Therefore, the pretreatment method has an important influence on the chemical modification of plant fibers. In this paper, Jute fibers were successively treated by particular continuous screw-extrusion steam explosion (CSESE). The effects on the morphological ructure, composition, thermal and crystalline properties of jute fibers before and after treated were investigated. Scanning electron microscopy (SEM) showed that the morphological structure changed significantly after CSESE pretreatment, the diameter was smaller, the surface cracks and the specific surface area increased. There was no new functional groups appeared in fourier transform infrared spectroscopy (FTIR). Composition analysis demonstrated that the content of hemicellulose and extractive decreased, but cellulose and lignin increased. The crystallinity of JSE increased from 66.31 % to 70.19 %. X-ray photoelectron spectroscopy (XPS) suggested that the cellulose and lignin content increased. Thermogravimetric analysis (TGA) demonstrated that the initial decomposition temperature of JSE increased from 334.4 to 355.2°C. DMA indicated that the Tg of JSE reduced from 92.6 to 90.0°C. Therefore, for jute fiber, the CSESE pretreatment is an effective and promising pretreatment method for further chemical modification, biofuels and chemical products.

In this study, an environmentally friendly biosorbent deacetylated konjac glucomannan conjugated soy protein isolate (abbreviated as DKGM-C-SPI) was prepared for Cu(2+) ions removal from aqueous solution. Scanning electron microscopy, Fourier transform infrared spectroscopy and zeta potential analysis revealed successful conjugation of soy protein isolate (SPI) onto deacetylated konjac glucomannan (DKGM) matrix. A comparative adsorption performance of DKGM-C-SPI and DKGM was tested to remove Cu(2+) ions from aqueous solution. DKGM-C-SPI showed the desired adsorption performance for Cu(2+) ions. The adsorption equilibrium of DKGM-C-SPI was achieved within 30 min. The adsorption behavior of DKGM-C-SPI followed a pseudo-second-order reaction model. The maximum Cu(2+) ion adsorption capacities obtained from the Langmuir isotherms fit were shown to be 62.50 mg g(-1) for DKGM-C-SPI and 12.23 mg g(-1) for DKGM. This impressive increase about 5 times in Cu(2+) ion adsorption capacity is attributed to the strong Cu(2+) ion chelating ability of the soy protein isolate (SPI) on the DKGM matrix. These results confirm that the DKGM-C-SPI biosorbent has a potential for Cu(2+) ion extraction from wastewater.

A new concept combining both thermoplastic binder co-cure and prepreg interlayer is proposed and investigated for fusion bonding of thermosets composite structures. Three different thermoplastic binders were co-cured respectively onto the surface of the carbon fiber reinforced epoxy (CF/Epoxy) composite laminates to form an auxiliary medium for electrical resistance welding. The carbon fiber reinforced binder (CF/Binder) prepreg interlayer, which is compression molded with a single layer of carbon fiber fabric sandwiched between two binder films, was designed as the heating element. Double cantilever beam (DCB) specimens were fabricated by fusion bonding of the CF/Epoxy composite laminates. The influence of the thermoplastic binders and the CF/Binder prepreg interlayers on the mode I interlaminar fracture toughness (GIC) and the morphology of the fracture surface were studied respectively by double cantilever beam test and scanning electron microscope. The results indicate that a maximum average delamination strength GIC of 1879.6 J/m2 was obtained in the case of the AX8900 binder welded specimens using twill weave fabric heating element. Three types of failure pattern can be visually and microscopically observed, i.e. interfacial-type failure, cohesive-type failure and interlaminar-type failure. Keywords: Laminates, Fracture toughness, Mechanical testing, Joints/joining

Soy protein isolate (abbreviated as SPI) was chemically immobilized on deacetylated konjac glucomannan (abbreviated as DKGM) in the current work. The obtained porous SPI/DKGM composite beads were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectra (FTIR) and zeta potential analysis. Adsorption performances of porous SPI/DKGM composite beads were tested to remove methylene blue from aqueous solution. Benefiting from the combined merits of SPI, high adsorption capacity and fast adsorption of methylene blue (MB) by porous SPI/DKGM composite beads are achieved. The maximum methylene blue adsorption capacities were shown to be 272.4 mg g −1 for porous SPI–DKGM composite beads. These results confirm that the porous SPI–DKGM composite beads have a potential for methylene blue removal from wastewater.

Objective: To optimize the preparation technology and matrix ratio of Sanqi hemostatic spongia. Methods: The effects of Twain 80, formaldehyde and twelve sodium alkyl sulfate on the matrix formability of the spongia were investigated by the L9 (33) orthogonal test, and the optimum ratio of the matrix was optimized through the water absorption, the thickness uniformity, the softness and the color degree. The orthogonal test results showed that the matrix ratio was Twain 80 1.4g, formaldehyde 1.6 mL, sodium dodecyl sulfate 1.0 g, and Sanqi hemostatic spongia was superior when the proportion of other substrates was fixed. Conclusion: Sanqi hemostatic spongia was produced by orthogonal test and matrix ratio is stable, uniform in thickness and good in quality.

I kappa B kinase β (IKKβ) is one of the primary targets to regulate canonical NF-κB activity. The misregulation of NF-κB is associated with various diseases, including chronic inflammation and cancers. Most of the known IKKβ inhibitors target its active form and suffer from poor selectivity. In the present study, we aim to design inhibitors that can bind to the IKKβ inactive form and block its activation. We identified a potential allosteric site between the kinase domain (KD) and ubiquitin-like domain (ULD) of human IKKβ and used it to virtually screen a chemical library for allosteric inhibitors. Among the 133 compounds tested, 16 inhibited NF-κB activity by over 50% at 50 μM in a reporter gene assay. Further quantitative measurements and cytotoxicity study gave one compound

The fouling mechanisms of traditional Chinese medicine (TCM) extract produced by ultrafiltration (UF) have been investigated. A laboratory scale crossflow membrane filtration unit was used to conduct the experimental study. The rejection of the four types of macromolecules present in TCM extract is more than 80% and the transmittances of the active ingredients are more than 70%. Two models were applied to quantify and analyze the fouling mechanism. A resistance-in-series model was applied to determine the main factor responsible for fouling resistance. The experimental results showed that reversible fouling resistance mechanisms, including concentration polarization and cake layer resistance, were the principal causes of the membrane fouling. A filtration-blocking model was also utilized to analyze the predominant fouling mechanism. The results showed that the flux decline during UF of the TCM extract could be well described by the combined cake-complete model. The model fit well to data measuring the permeate volume as a function of time under a wide range of operating conditions. This fit analysis indicates that the development of membrane fouling was a dynamic process that started with pore blocking at the initial stage of filtration and followed by continuous cake layer formation.

Morphological characteristics and elemental fingerprints were compared in Chinese mitten crabs(Eri-ocheir sinensis) from three lakes(Taihu Lake,Shijiu Lake and Gucheng Lake) in Jiangsu Province.Truss network analysis using 16 length measurements suggested that crabs from the three lakes could not be reliably character-ized based on morphological characteristics.The accuracy rates yielded by discriminant analysis were 70% for crabs from Taihu Lake,90% for those from Shijiu Lake,and 80% for those from Gucheng Lake.An Agilent 7500ce ICP-MS was used to measure the concentrations of 21 chemical elements(Na,K,Ca,Fe,Mg,Sr,Ag,Al,As,Ba,Cd,Co,Cr,Cu,Mn,Mo,Ni,Pb,Se,Tl and Zn) in the third pereiopod of the crabs from the three lakes.The concentrations of Cr,Co,As,Se,Cd,Pb,Tl,Ag,Mo,and Ni were below the detection limit.However,in contrast to the morphological analysis,the origin of the crabs from the three lakes could be consistently identified from their elemental fingerprints.The corresponding accuracy rates yielded by discriminant analysis were 100% for crabs from Taihu Lake,80% for those from Shijiu Lake,and 100% for those from Gucheng Lake.We conclude that the approach of using environmentally determined elemental fingerprints in the third pereiopod of the crabs is a potentially valid method for identifying the geographical origin of Chinese mitten crabs.

To understand the effect of the catalyzer in phenolic matrix on the structure and performance of carbon/carbon composite, the three elements of boron, iron and chromium are used to modify carbon matrix resin. The results show that the introduction of the catalyzer changes the degree of graphitization, density and interface bonding conditions of the sample. The electric conductivity, mechanical property and tribological properties of carbon/carbon composite are closely related to matrix carbon containing the catalyzer. This is specifically represented as that the graphitizing by catalyzer can significantly reduce the resistivity of composites; graphitizing by catalyzer improves the fracture toughness of composites but will reduce the flexural strength; appropriate catalyzer can improve the friction performance of carbon/carbon composite.

The bipolar plate is one of the most important components in proton exchange membrane fuel cell. In this article, the graphite/polymer composite bipolar plates have been developed by compression molding technique. The study on effects of different resin types on the electrical conductivity, mechanical property, and corrosion performance of the composite bipolar plates shows that the properties of graphite/novolac epoxy (NE) plate are all better than those of graphite/phenol formaldehyde resin plate. The triple continuous structure provides graphite polymer blends with high electrical conductivity, high flexural strength, less porosity, and high density. Most of the properties, such as electrical conductivity, flexural strength, water adsorption, porosity, and so on, are affected by the properties of the polymer. The graphite/NE composite bipolar plate when used in the unit fuel cell assembly showed single-cell performance comparable to that of the commercially available graphite bipolar plates.

Porous carbons used for electric double layer capacitors (EDLCs) were prepared by chemical blending of phenolic resin (PF) and adipic diacid (DA). Chemical reaction of PF with diacid is manifested by a shift of carbonyl stretching peak of diacid to a higher frequency in FT-IR spectra and a higher decomposition temperature of diacid in TG curves. The influences of the ratio of w(DA) to w(PF) on pore structure, adsorption behavior and capacity per- formance were investigated. The specific surface area and total pore volume increase with the ratio of w(DA) to w(PF) at first and then decrease, reach the maximum at the value of w(PF)/w(DA), which are 550 cm 2 /g and 0.27 cm

Based on the embedded-atom method, molecular dynamics simulations have been performed to study the structural features of Al and Cu in the liquid and solid states during rapid solidification. The calculated pair correlation functions above the melting points of Al and Cu are found to be in good agreement with experiment, especially for Cu. The results show that the EAM can correctly and efficiently predict the glass transition and crystallization during rapid solidification from liquid metals, and can also describe microstructures of liquids, supercooled liquids, glasses and crystalline phases. In addition, structural analysis using bond orientational order and pair analysis techniques have been made in detail, and the effect of cooling rate on microstructures during rapid solidification has been analysed.

The local orientational order in binary liquid Li-In alloys at a constant temperature has been systematically studied using molecular dynamics simulations combined with potential mapping techniques. The generalized non-local model pseudopotential theory has been chosen as the fundamental theory for our calculation. Both the orientational order parameters and pair analysis approach have been adopted to examine the characterization of structures in binary liquid Li-In alloys. It demonstrates that the mapping procedure produces a significant image enhancement of the short-range order, and the third-order invariant of the spherical harmonics is much more sensitive to the icosahedral symmetry than is the quadratic invariant. In addition, the bonded pairs with various symmetries, icosahedra, defective icosahedra, etc, formed in liquid Li-In alloys are also examined and the relationship between these quantities and compositions are investigated. The results further show that distributions of the attractive part of the potentials play an important role in characterizing liquid structures. Finally, a detailed discussion of the results has been given.

Ab initio molecular orbital theory with split-valence (4–31G, 6–31G), and split-valence plus polarization (6–31G*) basis sets and with electron correlation incorporated using Moller-Plesset perturbation theory terminated at second (MP2), third (MP3) and fourth (MP4) order has been used to investigate the isomerization and unimolecular rearrangement channels of monothioformic acid. All the optimized structures at the various basis levels are quite similar, and the calculated geometries of thiolformic acid are in good agreement with its known experimental geometries. The energy differences between the cis and trans isomers calculated at the MP4/6–31G∗∗//RHF/6–31G∗ level are 22.1 kJ mol−1 for the thionformic acid and 5.3 kJ mol−1 for the thiolformic acid. The latter value is very close to the reported experimental value of 2.8 kJ mol−1. In three possible unimolecular reactions, the best results (MP4/6–31G∗∗//RHF/6–31G∗ plus scaled zero-point energy) gave a barrier height of 133.3 kJ mol−1 for the 1,3-intramolecular hydrogen shift (pathway A). The barrier heights of two 1,2-intramolecular hydrogen shifts for the rearrangements of trans-thionformic acid and traras-thiolformic acid to the thiohydroxy hydroxy carbene (pathways B and C) were calculated as 320.5 kJ mol−1 and 335.2 kJ mol−1, respectively. From the barrier heights these results demonstrate that pathway A, i.e. that via a 1,3-hydrogen shift, is much more favourable than that via two successive 1,2-hydrogen shifts (pathways B and C', the inverse reaction of C) for the rearrangement of the trans-thionformic acid to the trans-thiolformic acid.

Inland fishery carbon sink(IFCS)refers to the process and mechanism in which fishery organ-isms absorb and sequestrate CO2 sequestrate CO2 in the water and remove it from the water,and conse-quently,inland carbon sink fishery(ICSF) will be any fishery activity that effectively promotes a relative increase of IFCS.Phytoplankton fixes CO2 through photosynthesis and converts it into organic carbon.Quite much of it is taken up by major freshwater herbivorous and filter-feeding fish and mussels,and ac-cordingly,carbon can be cascaded through aquatic food webs and removed by capture fisheries and aqua-culture.Therefore,ICSF can not only provide large quantities of nutritious food,but also play a critical role in carbon sequestration and removal.Carbon in freshwater ecosystems can be made up of different chemical components,like particulate organic and inorganic carbon,dissolved inorganic and organic car-bon,which are convertible with high dynamics.It is noteworthy that unsustainable fishing related activities will jeopardize the potential capacities and even ecosystem services of IFCS.Therefore,the importance of IFCS and ICSF must be highlighted.A more recent study suggested that aquaculture ponds(110 830 km2) sequester an estimated 16.6 million tonnes/year of carbon globally,and the most carbon sequestration oc-curs in Asia and particularly in China(94% and 55.9% of global aquaculture pond area,respectively).Fishery will be the only controllable industry that is possible to effectively increase the carbon sink capac-ity in aquatic ecosystem,and the carbon sink fishery will be the only carbon sink industry in aquatic eco-system.To better understand the mechanism of carbon sink/source,the current focus of study should be on the natural laws of carbon cycles in inland fishery ecosystem(including natural waters and ponds),form conversion between different chemical components,the carbon footprint for each of the different inland fisheries and aquaculture activities,and the corresponding assessment methods and models.At the same time,attention should also be paid to calculating realistic estimates of CO2 fluxes in inland fishery waters and at the water-atmosphere interface,understanding the dynamics of carbon sink/source,and establish-ment of the information platform for environmental carbon/biological carbon/carbon fluxes of ICSF.

It is of interest to synthesize the M-Ba-Y-Cu-O system, where M is a magnetic element, in order to investigate its superconductivity mechanism and the relation between the superconductivity and the magnetism. We study the effect of a typical magnetic element, iron, on the superconductivity of the Ba-Y-Cu-O system.