Search

Methane is one of the most important gases leading to the earth’s air pollution. Ventilation air methane(VAM) is an important part of the gas discharged into the atmosphere. The volume concentration of methane is generally less than 0.5% in coal mines. Recycling low concentration is facing challenges. To explore the law of low concentration methane enrichment, the enrichment tower for methane was designed and manufactured. The experiment was divided into two types - free diffusion and weak eddy enrichment, and eight kinds of low concentration gas experimental program. Under free diffusion conditions, the maximum methane concentration of the top (middle) tower is 0.64% (0.53%). In the condition of weak eddy field, the maximum methane concentration is 0.67% (0.69%) in the top (middle) tower. The effect of methane enrichment in the weak eddy field is obvious. Methane enrichment method under the eddy current field can greatly increase methane enrichment efficiency and achieve the goal of CMM (coal mine methane) power generation.

In the present study, biocomposite films with incorporated Perilla frutescens (L.) Britt. essential oil (PEO) were prepared using the solvent casting method. Perilla essential oil concentrations at 0.2%, 0.6%, and 1.0% (v/v) had a significant effect on the physical, chemical, and antibacterial activity of the films. Films with PEO exhibited a significant decrease (p

In order to solve the shortcomings of the traditional curing agent in the treatment of composite heavy-metal-contaminated soil with the solidification and stabilization method, a new type of cementing material A was used as a curing agent, and the Pb, Cd, Cu composite heavy-metal-contaminated soil was artificially prepared to carry out an experimental study on solidification and stabilization (SS) restoration by the mechanical properties test, leaching performance test, and microscopic test. The results show that in the range of test dosage, with the increase in the curing agent content, the unconfined compressive strength of the solidified body increased, and the resistance to deformation was enhanced. From the perspective of leaching characteristics, the new curing agent A had an excellent curing effect on the composite heavy-metal-contaminated soil. To achieve safe disposal, a curing agent content of 10% applies only for the soil heavily contaminated by heavy metals. The curing agent A could significantly reduce the content of acid-extractable heavy metals after solidifying the heavy metal Pb, Cd, and Cu composite contaminated soil and effectively converted it into a residue state. The solidified phase contained hydrated products such as calcium silicate hydrate (CSH) and ettringite (AFt). These hydrated products can inhibit the leaching performance of heavy metal ions through adsorption, encapsulation, and ion exchange. The study provides a feasible method and reference for the solidification, restoration, and resource utilization of heavy-metal-contaminated soil in the subgrade.

BACKGROUND Perilla EO possess high antioxidant, antimicrobial and insecticidal activities, and have proven to be more reliable than chemically synthesized food preservatives. Nevertheless, EOs have disadvantages of facile photo-degradation and oxidation which limits their use in agriculture and food industries. Microencapsulation technology that generates a polymeric coating surrounding EOs could overcome these disadvantages. RESUILS The EO concentration had a significant effect on encapsulation efficiency (EE) and loading capacity (LC). The best encapsulation conditions were obtained with 2% v/v EO, for which EE and LC were 57% and 36%, respectively. EO-loaded microspheres exhibited a crimped surface with phanic lumps by scanning electron microscopy. Thermal stability experiments revealed droplets began to decompose sharply at 108°C, with a 61% weight loss that was much lower than EOs of 98%. EO-loaded microcapsules demonstrated good antibacterial activity. Strawberry preservation studies showed EO-loaded microcapsules could significantly inhibit strawberry decay, maintain the quality of strawberries, and prolong the shelf life. CONCLUSION Perilla EO-loaded microcapsules were successfully prepared by ionic gelation and were effective at inhibiting several bacterial strains. EO-alginate microcapsules could effectively delay the volatilisation of EO. Perilla EO-loaded microcapsules therefore have potential for use as an antimicrobial and preservative agent in the food industries.

A vertically porous Ni(OH) 2 /Ni film grown on carbon cloth was fabricated as the electrode of supercapacitors. Dense Ni film was first deposited on carbon cloth by magnetic sputtering, following by etching treatment and electrochemical oxidation to form vertically porous Ni(OH) 2 /Ni/CC composite. The Ni(OH) 2 /Ni/CC composite had a specific capacitance of 1760 F g −1 at 2 mV s −1 and the capacitance retention of 88% after 3000 cycles at 20 A g −1 . The special structure of Ni(OH) 2 /Ni/CC composite may be the main reason for its high energy storage performance.

To reduce the size of Ni(OH)2 aggregates is an effective way to improve their capacitive performance for the electrodes of supercapacitors. The ultrasmall Ni(OH)2 aggregates (1–2 nm) on active carbon (AC) can be obtained by depositing the soluble precursor of Ni(OH)2 on AC at low temperature. The Ni(OH)2/AC samples were characterized by SEM, TEM, XRD and XPS. The specific capacitance of ultrasmall Ni(OH)2 aggregates in the Ni(OH)2/AC composite can reach 2949 F g−1 at a scan rate of 20 mV s−1, which is higher than its theoretical specific capacitance (2382 F g−1). Ni(OH)2 aggregates supported on carbon cloth can also exhibit superior specific capacitance as a bind-free flexible electrode. The capacitive, rate and cycling performance of ultrasmall Ni(OH)2 aggregates on AC are excellent, revealing the great potential of ultrasmall sized materials in energy storage.

Three-dimensionally porous metal materials are often used as the current collectors and support for the active materials of supercapacitors. However, the applications of vertically porous metal materials in supercapacitors are rarely reported, and the effect of vertically porous metal materials on the energy storage performance of supported metal oxides is not explored. To this end, the Mn3O4-vertically porous nickel (VPN) electrodes are fabricated via a template-free method. The Mn3O4-VPN electrode shows much higher volumetric specific capacitances than that of flat nickel film supported Mn3O4 with the same loading under the same measurement conditions. The volumetric specific capacitance of the vertically porous nickel supported Mn3O4 electrode can reach 533Fcm(-3) at the scan rate of 2mVs(-1). The fabricated flexible all-solid microsupercapacitor based on the interdigital Mn3O4-VPN electrode has a volumetric specific capacitance of 110Fcm(-3) at the current density of 20μAcm(-2). The capacitance retention rate of this microsupercapacitor reaches 95% after 5000 cycles under the current density of 20μAcm(-2). The vertical pores in the nickel electrode not only fit the micro/nanofabrication process of the Mn3O4-VPN electrode, but also play an important role in enhancing the capacitive performances of supported Mn3O4 particles.

Ultrafast rechargeable Li-ion batteries are most urgently needed for personal electronics and commercial application since they could fuel various energy applications. These days, much time and efforts have been paid on the research of ultrafast rechargeable Li-ion batteries, however, less breakthrough was appeared. In this manuscript, the CuCr2O4@RGO, a new-type of nanocomposite material, demonstrates a promising future application when it was used as an anode material of the Li-ion batteries. The Li-ion batteries displays a specific capacity of about 410 mAh g−1 and a coulombic efficiency of approximately 98 % at the discharge/charge current rate of 1000 mA g−1. We also found that the batteries constructed by CuCr2O4@RGO nanocomposites as active anode materials can be fully charged within 5 min, with a current density of 4000 mA g−1 and strive against more than 900 cycles without capacity decay. All the results indicate that the CuCr2O4@RGO nanocomposites with spinel structure of the mixed transitional metal oxide are promising for the anode materials of ultrafast rechargeable Li-ion batteries.

The role vegetation restoration and succession play in regulating Nitrogen (N) and Phosphorous (P) pools remains unexplored and poorly understood. To examine the effects of vegetation restoration and succession from a shifting sand dune to restored vegetation at different ages (23, 33, 50, and 58 years) on the dynamics and distribution of N and P pools in a soil-plant system, a comprehensive field investigation was conducted and N(P) concentrations and densities of soil, shrubs (including leaves, new branches, aging branches, and roots), and grass (including aboveground, roots, and litter) at each site were analyzed and quantified. We found that total N (TN) and total P (TP) density for the plant-soil system, in live shrub biomass as well as soil TN (STN) density in subsoil (10–100 cm), decreased between 23 and 50 years, and then increased from 50 to 58 years. STN and soil TP (STP) densities in topsoil (0–10 cm), and N and P densities of herbage and dead shrubs, continued to increase with restoration. N and P were primarily stored in soils and accounted for 89.83%–92.06% and 99.33%–99.48% of the TN and TP pools, respectively. In the first 23 years, live shrubs made up the second largest N and P pools, however, herbage made up the second largest N and P pools after 23 years. The ratios of N and P in herbage to TN and TP density increased from 3.71% to 6.31%, and 0.33%–0.43%, gradually approaching the native site (6.39% and 0.46%). The ratios of N and P in live shrubs to TN and TP density in the soil-plant system decreased from 4.55% to 1.08% and from 0.33% to 0.13%. Our results indicated that the restored ecosystem was a N(P) source from 0 to 50 (0–23) years, and a N(P) sink from 50 to 58 (23–58) years, with strong potential for accumulating more N (147.18 g m−2) and P (102.67 g m−2) to reach the natural site levels. These results suggest that vegetation restoration and succession may profoundly alter N and P geochemical cycles through N(P) redistribution in a temperate desert plant-soil system. Proper N and P addition at the initial stage of vegetation restoration may promote the recovery of desertified land.

The white rot disease caused by Botryosphaeria dothidea threatens apple production in Bohai bay area and along the Yellow River of China, where disease control is largely dependent on fungicides such as tebuconazole. A total of 146 isolates of B. dothidea obtained from different apple orchards in six provinces were tested for their sensitivity to tebuconazole, carbendazim and iprodione. The EC50 values of all tested isolates for tebuconazole were from 0.035 to 1.415 μg/mL. The broad range of EC50 values of tebuconazole suggests an obvious variation among the 146 isolates. Isolate HB13 (EC50 = 1.415 μg/mL) showed reduced sensitivity to tebuconazole, with an EC50 value significantly higher than those of the other 145 isolates tested. The low sensitivity of HB13 was stable after 15 generations, and this isolate showed similar pathogenicity as susceptible strains. EC50 correlation analysis indicates no cross resistance between tebuconazole and carbendazim and iprodione. Field efficacy trials showed that tebuconazole remains very effective for apple white rot control in China.

Response surface methodology (RSM) was used to optimize ultrasound-assisted extraction (UAE) conditions of perilla seed oil including extraction temperature, time, and liquid-to-solid ratio. The results revealed that extraction time had a significant effect on oil yield. Based on the RSM results, the optimum conditions included an extraction temperature of 41.26 °C, an extraction time of 17.11 min, and a liquid-to-solid ratio of 7.02:1. Under these conditions, the maximum oil yield was 36.27%. The physical and chemical characteristics of perilla oil were evaluated. Perilla had high iodine and low acid and peroxide values, indicating that the seed oil has the good qualities of an edible oil and can be stored for a long period of time without deterioration. The fatty acid profile of perilla oil included saturated (6.99%), monounsaturated (16.76%), and polyunsaturated fatty acids (76.25%). Linolenic (63.93%), linoleic (12.32%), and oleic acid (16.65%) were the main fatty acids in perilla seed oil. The thermal stability experiments revealed that perilla oil decomposition began at 320.2 °C, with two stages at 421.3 °C and 466.6 °C. Based on its physical and chemical properties, perilla oil should have applications in the cosmetic, pharmaceutical, and food industries.

Response surface methodology (RSM) was used to optimize the ultrasound-assisted extraction parameters of perilla protein isolate (PPI), which has functional properties. A central composite experimental design was applied to investigate the effects of three factors (ultrasonic power, extraction time, and liquid-to-solid ratio) on six responses: protein yield, water solubility index (WSI), water absorption capacity (WAC), oil holding capacity (OHC), emulsifying activity (EA), and foaming ability (FA). Based on the RSM results, the optimum conditions were an ultrasonic power of 206 W, and extraction time of 32.4 min, and a liquid-to-solid ratio of 10.34:1. Under these conditions, PPI had high protein yield (26.1%) and functional properties (55.2% WSI, 3.6% WAC, 1.76 g/g OHC, 60.25 m2/g EA, 63.2% FA). Differential scanning calorimetry revealed that PPI was slightly denatured at 75.16 °C, and the amount of heat required to induce this denaturation was 0.03 J/g. SDS-PAGE presented protein bands that ranged from 14.4 to 66.2 kDa. Based on its functional properties, PPI can be used in the food industry.

For the development of effective and safe gene carrier based on starch, the amylose from potato starch was azidized by reacting with 3-azidopropylamine in the presence of N, N'-carbonyldiimidazole and then conjugated with propargyl focal point poly(amidoamine) (PAMAM) dendrons by a Cu(I)-catalyzed azide-alkyne cycloaddition. Such a cationic dendronization was verified by Fourier transform infrared spectroscopy and proton nuclear magnetic resonance analyses. For the resultant amylose conjugates with various contents and generations of PAMAM dendron, their buffering capacity, binding ability with plasmid DNA and in vitro cytotoxicity were investigated. These amylose conjugates were found to exhibit good buffering capacity and biocompatibility. In particular, they could condense effectively plasmid DNA into the nanocomplexes, as confirmed by agarose gel electrophoresis, zeta potential, and particle size analyses as well as transmission electron microscopy observation. For their nanocomplexes with plasmid DNA, the in vitro transfection properties in human embryonic kidney 293T cells were studied by fluorescence microscopy and flow cytometry. It was found that the transfection efficiency could be optimized by the dendronization extent of amylose and the complexation extent of dendronized amylose with plasmid DNA.

In recent years, immobilization agents were introduced into organic contaminated soil remediation and more and more materials were screened and used as the immobilizing carrier. However, effect of the decomposition of the immobilizing carrier on the bioremediation was rarely concerned. Therefore, the decomposition experiment of immobilizing carrier -corncob was carried out in the lab with the efficient degradation fungi - Mucor mucedo (MU) existing, and polycyclic aromatic hydrocarbons (PAHs) residues E4/E6 of the dissolved organic matter and microbial diversity during the decomposition process were studied. The results showed that: a) during the decomposition, the degradation of pyrene (Pyr) was mainly in the first 28 d in which the content of extractable Pyr decreased rapidly and the highest decrease was in the treatment with only MU added. b) Anslysis of E4/E6 changes showed that rich microorganisms could promote aromatization and condensation of humus. c) From the diversity index analysis it can also be seen that there is no significant difference in effects of PAHs on the uniformity of microorganisms. These results will not only be useful to have a better understanding of the bioavailability of contaminants adsorbed to biodegradable carriers in PAHs contaminated soil remediation, but also be helpful to perfect the principle of immobilized microbial technique.

Vertical alligned carbon nanotube@MnO2 (VACNT@MnO2) arrays grown on carbon cloth were prepared as high performance flexible electrodes for supercapacitors. VACNTs first grew on carbon cloth with the method of plasma enhanced chemical vapor deposition (PECVD) to obtain firm connection between CNTs and carbon cloth, and δ-MnO2 nanosheets were deposited on the surface of VACNTs to form a VACNT@MnO2 core–shell structure. The VACNT@MnO2 on carbon cloth (VACNT@MnO2/CC) exhibited a remarkable specific capacitance (235 F g−1 at the scan rate of 2 mV s−1 based on the total mass of VACNTs and MnO2), an excellent rate performance with a specific capacitance of 188 F g−1 at 100 mV s−1 and a stable cycling ability (nearly 100% retention after 5000 charge/discharge cycles at 5 A g−1). The fabricated symmetric supercapacitor from the self-supported VACNT@MnO2/CC without any additive reagents had the same electrochemical energy storage performance when this supercapacitor was bent 180°, revealing the excellent flexibility of our prepared flexible electrodes. The excellent performances in electrochemical properties and flexibility mainly originated from a strong mechanical coupling between CNTs and CC as well as sufficient contact between the electrolyte and the surface of MnO2 nanosheets in such an arrayed structure.

4-(Chloromethyl) phenyltrichlorosilane was used to modify silica spheres to obtain a sensitive and selective nanoparticle powder for detecting latent fingerprints. Various analytical techniques were used to characterize the nanoparticles and to show that the structure and properties are well-suited for forensic science. The synthesis of the particles was optimized based on the performance in terms of detection and the development of a test set of latent prints. The new material offers simple synthesis, convenient use for routine casework, and low price. These advantages suggest potential application for crime scene investigations.

Response surface methodology (RSM) was used to optimize ultrasound-assisted aqueous enzymatic extraction (UAAEE) conditions for perilla seed oil. Under the optimum conditions—which were a liquid-to-solid ratio of 4.4:1, a hydrolysis time of 2.66 h, a hydrolysis temperature of 50.87 °C and an ultrasound treatment time of 24.74 min—an oil yield of 31.34% was obtained. Comparisons of the physicochemical characteristics of oil obtained using UAAEE with those of oil obtained by solvent extraction (SE oil) and cold pressing extraction (CPE oil) revealed similar refractive indices and saponification values, but UAAEE oil had a higher iodine value and better stability against oxidation, with a low peroxide value. UAAEE oil contained higher levels of beneficial α-linolenic acid and phenolics than SE oil or CPE oil, and it also had superior efficiency in scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals.

Perilla is an edible medical plant with rapidly increasing acreage in China. In this study, we investigated the potential of perilla stalks (PSs) as an alternative substrate for the cultivation of oyster mushrooms (Pleurotus ostreatus). P. ostreatus was cultivated on cottonseed hulls (CSH) alone or mixed with PSs in different ratios. The production parameters, physical characteristics, nutritional values, and antioxidant activity of mushrooms cultivated on different substrate mixtures were determined. The addition of PSs to CSH significantly improved the growth rate, yield, biological efficiency, and proximate composition and shortened the cultivation cycle. Cultivation on PSs alone increased the amino acid content in P. ostreatus fruiting bodies and the antioxidant activity of mushroom extracts. The PS75 (25% CSH+75% PS) substrate was deduced to be the most effective substrate on the basis of yield and biological efficiency obtained in a large area where perilla had been planted. The results demonstrate that mixtures of PS with CSHs could be used as novel, practical, and easily accessible alternative substrates for P. ostreatus cultivation.

Sitagliptin phosphate, a novel DPP-IV inhibitor of T2DM, has been synthesized via 12 linear steps, in an overall yield of 26%. The key step is the coupling reaction of 2,4,5-trifluorophenylmagnesium bromide with a chiral aziridine derivative, which was prepared from l-homo-serine by simple steps.

The title compound (III) is obtained with excellent diastereoselectivity under optimized and improved Simmons—Smith reaction conditions.

Two-dimensional materials are characterised by a number of unique physical properties which can potentially make them useful to a wide diversity of applications. In particular, the large thermal conductivity of graphene and hexagonal boron nitride has already been acknowledged and these materials have been suggested as novel core materials for thermal management in electronics. However, it was not clear if mass produced flakes of hexagonal boron nitride would allow one to achieve an industrially-relevant value of thermal conductivity. Here we demonstrate that laminates of hexagonal boron nitride exhibit thermal conductivity of up to 20 W/mK, which is significantly larger than that currently used in thermal management. We also show that the thermal conductivity of laminates increases with the increasing volumetric mass density, which creates a way of fine-tuning its thermal properties., Comment: 6 pages, 4 figures

Cellulose fibers from cellulose/1-ethyl-3-methylimidazolium acetate solution were prepared by wet spinning with increasing extrusion speeds and draw ratios. The effects of spinning speeds on the structures and mechanical properties of these fibers were investigated by using scanning electron microscopy, wide angle X-ray diffraction, birefringence, thermogravimetric analysis, tensile-fineness tester, and wet friction. The results showed that the crystallinity, orientation, and mechanical properties of the fibers were improved with increasing draw ratio. The break draw ratios, degrees of crystallinity and orientation, tenacities, and wet friction time of the cellulose fibers decreased with increasing extruding speeds. The wet friction time decreased with increasing draw ratio and decreased faster under higher extrusion speed. Due to the high dope concentration and the increased draw ratio, the maximum tenacity of the regenerated cellulose fibers reached 2.73 cN/dtex. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40225.

A simple and efficient synthetic route to 2-(3-hydroxy-1-adamantyl)-2-oxoacetic acid is described by a direct oxidation reaction of adamantan-1-yl-ethan-1-one which could be prepared by a Grignard ...

The title compound (III) is obtained with excellent diastereoselectivity under optimized and improved Simmons—Smith reaction conditions.

The development of alien substitution lines is important for transferring useful genes of exotic species into bread wheat. In situ hybridization, SSR and EST-SSR marker analysis were used to identify a wheat–Thinopyrum intermedium substitution line designated as Zhong 199. Zhong 199 was detected with the chromosome number 2n=42 and stable agronomic traits were evaluated during the 2012 field harvest season. Genomic in situ hybridization analysis with the genomic Th. intermedium DNA as a probe showed that Zhong 199 contained a pair of Th. intermedium chromosomes. Fluorescence in situ hybridization, using a repetitive sequence, pAs1, derived from Aegilops squarrosa L., indicated the replacement of chromosome 2D of wheat in the wheat–Th. intermedium substitution line. Seven SSR markers specific for chromosome 2D of wheat further confirmed that the substituted wheat chromosome was 2D in the substitution line. Such result was also confirmed by using EST-SSR marker analysis. This study provided some useful information for effective exploitation of the source of genetic variability for the improvement of wheat.

Response surface methodology (RSM) was used to optimize ultrasound-assisted extraction (UAE) of functional components from perilla leaves. The factors investigated were ethanol concentration, extraction temperature, and extraction time. The results revealed that ethanol concentration had significant effects on all extraction parameters. Based on the RSM results, the optimal conditions were an ethanol concentration of 56%, a UAE temperature of 54 °C, and a UAE time of 55 min. Under these conditions, the experimental TPC (total phenolic content), RA (rosmarinic acid), FRAP (ferric reducing antioxidant power) and DPPH (1,1-diphenyl-2-picrylhydrazyl) values were 48.85 mg GAE/g DW (mg gallic acid equivalent /g of dry weight), 31.02 mg/g DW, 85.55 μmol Fe 2+ /g DW and 73.35%, respectively. The experimental values were in agreement with those predicted by RSM models, confirming suitability of the model employed and the success of RSM for optimization of the extraction conditions. Keywords