The cyclic hydrogenation technology in a direct coal liquefaction process relies on the dissolved hydrogen of the solvent or oil participating in the hydrogenation reaction.Thus,a theoretical basis for process optimiz...The cyclic hydrogenation technology in a direct coal liquefaction process relies on the dissolved hydrogen of the solvent or oil participating in the hydrogenation reaction.Thus,a theoretical basis for process optimization and reactor design can be established by analyzing the solubility of hydrogen in liquefaction solvents.Experimental studies of hydrogen solubility in liquefaction solvents are challenging due to harsh reaction conditions and complex solvent compositions.In this study,the composition and content of liquefied solvents were analyzed.As model compounds,hexadecane,toluene,naphthalene,tetrahydronaphthalene,and phenanthrene were chosen to represent the liquefied solvents in chain alkanes and monocyclic,bicyclic,and tricyclic aromatic hydrocarbons.The solubility of hydrogen X(mol/mol)in pure solvent components and mixed solvents(alkanes and aromatics mixed in proportion to the chain alkanes+bicyclic aromatic hydrocarbons,bicyclic saturated aromatic hydrocarbons+bicyclic aromatic hydrocarbons,and bicyclic aromatic hydrocarbons+compounds containing het-eroatoms composed of mixed components)are determined using Aspen simulation at temperature and pressure conditions of 373–523 K and 2–10 MPa.The results demonstrated that at high temperatures and pressures,the solubility of hydrogen in the solvent increases with the increase in temperature and pressure,with the pressure having a greater impact.Further-more,the results revealed that hydrogen is more soluble in straight-chain alkanes than in other solvents,and the solubility of eicosanoids reaches a maximum of 0.296.The hydrogen solubility in aromatic ring compounds decreased gradually with an increase in the aromatic ring number.The influence of chain alkanes on the solubility of hydrogen predominates in a mixture of solvents with different mixing ratios of chain alkanes and aromatic hydrocarbons.The solubility of hydrogen in mixed aromatic solvents is less than that in the corresponding single solvents.Hydrogen is less soluble in solvent compounds containing heteroatoms than in compounds without heteroatoms.展开更多
Fine particulate matter produced during the rapid industrialization over the past decades can cause significant harm to human health.Twin-fluid atomization technology is an effective means of controlling fine particul...Fine particulate matter produced during the rapid industrialization over the past decades can cause significant harm to human health.Twin-fluid atomization technology is an effective means of controlling fine particulate matter pollution.In this paper,the influences of the main parameters on the droplet size,effective atomization range and sound pressure level(SPL)of a twin-fluid nozzle(TFN)are investigated,and in order to improve the atomization performance,a multi-objective synergetic optimization algorithm is presented.A multi-physics coupled acousticmechanics model based on the discrete phase model(DPM),large eddy simulation(LES)model,and Ffowcs Williams-Hawkings(FW-H)model is established,and the numerical simulation results of the multi-physics coupled acoustic-mechanics method are verified via experimental comparison.Based on the analysis of the multi-physics coupled acoustic-mechanics numerical simulation results,the effects of the water flow on the characteristics of the atomization flow distribution were obtained.A multi-physics coupled acoustic-mechanics numerical simulation result was employed to establish an orthogonal test database,and a multi-objective synergetic optimization algorithm was adopted to optimize the key parameters of the TFN.The optimal parameters are as follows:A gas flow of 0.94 m^(3)/h,water flow of 0.0237 m^(3)/h,orifice diameter of the self-excited vibrating cavity(SVC)of 1.19 mm,SVC orifice depth of 0.53 mm,distance between SVC and the outlet of nozzle of 5.11 mm,and a nozzle outlet diameter of 3.15 mm.The droplet particle size in the atomization flow field was significantly reduced,the spray distance improved by 71.56%,and the SPL data at each corresponding measurement point decreased by an average of 38.96%.The conclusions of this study offer a references for future TFN research.展开更多
Focusing on the use of imidazolium ionic liquids and quaternary ammonium salts-based deep eutectic solvents for the separation of phenols and nitrogen-containing heteroaromatics,the role of heteroaromatics as specific...Focusing on the use of imidazolium ionic liquids and quaternary ammonium salts-based deep eutectic solvents for the separation of phenols and nitrogen-containing heteroaromatics,the role of heteroaromatics as specific sites for hydrogen bond-based separation has been investigated.These environmentally friendly solvents are known for their ability to form hydrogen bonds with heteroatoms,a key aspect in separation processes.We quantified the hydrogen bond interaction energy to reach the threshold energy for efficient O-and N-heteroaromatics separation.This article provides an in-depth study of the structural nuances of different hydrogen bonding sites and their affinity properties while conducting a comparative evaluation of the separation efficiency of ionic liquids and deep eutectic solvents from a thermodynamic perspective.Results showed that phenols with dual hydrogen bonding recognition sites were easier to separate than nitrogen-containing heteroaromatics.Imidazolium ionic liquids were more suitable for the extraction of nonbasic nitrogen-containing heteroaromatics,and quaternary ammonium salts-based deep eutectic solvents are more effective for phenols and basic nitrogen-containing heteroaromatics,which was confirmed by Fourier transform infrared spectroscopy and empirical tests.Therefore,this study provides a theoretical basis for the strategy design and selection of extractants for the efficient separation of O-and N-containing aromatic compounds.展开更多
The mu oil tree(Vernicia montana Lour.) is a dioecious species, but the genetic mechanisms underlying its phenotypic sexual dimorphism are unclear. In this study, we determined two pivotal phases of sex differentiatio...The mu oil tree(Vernicia montana Lour.) is a dioecious species, but the genetic mechanisms underlying its phenotypic sexual dimorphism are unclear. In this study, we determined two pivotal phases of sex differentiation of mu oil tree via morphological and histological analyses of unisexual flowers:(Ⅰ) differentiation of male or female primordia to produce staminate flowers(SFs) or transient hermaphrodite flowers(HFs),and(Ⅱ) complete abortion of stamens in transient HFs to generate pistillate flowers(PFs). A total of 1621 sex-biased genes were identified by comparative transcriptome analysis which exhibited elevated rates of protein evolution than unbiased genes. The female-biased genes were enriched in the production of defense compounds while male-biased genes were focused on the production of viable pollens. Transcriptomebased analysis revealed that the differentially expressed genes(DEGs) between PFs and SFs in phase Ⅰ involved in abscisic acid(ABA), auxin(AUX), cytokinin(CK), ethylene(ET), and gibberellin(GA) biosynthesis and signaling showed higher expression levels in males than in females in general, whereas the DEGs involved in jasmonic acid(JA) and salicylic acid(SA) pathways displayed opposite expression patterns. Moreover,differentially expressed endogenous ABA, AUX, GAs, JA, and SA exhibited consistent biased expression patterns with the DEGs by UPLC-MSbased analysis. Exogenous application of an anti-ethylene plant growth regulator could promote the development of stamens in PFs and generated HFs. Comparative transcriptomic and hormonal analyses of PFs and SFs in phase Ⅱ indicated an increase in ET concentration when abortion of stamens in PFs occurred. This study suggested that phytohormones play key roles in sex dimorphism and ET may determine the development of stamens in PFs of mu oil tree, which provides an insight into plant sex differentiation mechanisms.展开更多
Objective：To analyze the incidence and mortality rates of laryngeal cancer in China from 2008 to 2012.Methods：Incident and death cases of laryngeal cancer were retrieved from the National Central Cancer Registry（N...Objective：To analyze the incidence and mortality rates of laryngeal cancer in China from 2008 to 2012.Methods：Incident and death cases of laryngeal cancer were retrieved from the National Central Cancer Registry（NCCR）database collecting from 135 cancer registries in China during 2008–2012.The crude incidence and mortality rates of laryngeal cancer were calculated by area（urban/rural）,region（eastern,middle,western）,gender and age group（0,1–4,5–9,…,85＋）.China census in 2000 and Segi’s world population were applied for age standardized rates.Join Point（Version 4.5.0.1）model was used for time trend analysis.Results：The crude incidence rate of laryngeal cancer was 1.86/100,000 ranked the 21st in overall cancers.The age-standardized incidence rates by China population（ASIRC）and by World population（ASIRW）were1.22/100,000 and 1.23/100,000,respectively.The crude mortality of laryngeal cancer in China was 1.01/100,000and it was the 21st cause of cancer-related death in overall cancers.Both the age-standardized mortality rates by Chinese standard population（ASMRC）and by world standard population（ASMRW）were 0.63/100,000.Incidence and mortality rates of laryngeal cancer were higher in males than in females and higher in urban areas than in rural areas.Middle areas had the highest incidence and mortality rates followed by eastern and western areas.Incidence and mortality rates of laryngeal cancer retained low level before age of 40 years old but increased greatly after and peaked in age group of 75.Incidence showed significant down trends in recent 10 years by 1.27%annually[95%confidence interval（95%CI）：–2.2%,–0.3%].Mortality declined in females sharply by 5.18%per year although stable in males and both sexes combined.Conclusions：Appropriate targeted prevention,early detection and treatment programs should be carried out to control the local burden of laryngeal cancer.展开更多
Two large landslides successively blocked the Jinsha River at the same location in Jiangda Village on October 10 and November 3,2018,respectively.The dynamic processes and possible interactions of the two landslides n...Two large landslides successively blocked the Jinsha River at the same location in Jiangda Village on October 10 and November 3,2018,respectively.The dynamic processes and possible interactions of the two landslides need to be studied to better understand the physical processes involved,and to provide information on future disaster mitigation.We investigated their force histories and sliding directions by inverting regional broadband seismograms.The scale of the October landslide was approximately three times that of the November event.The October event revealed a particularly strong deceleration force,which may have been caused by a collision between the sliding mass and ground surface.In contrast,the November event had a relatively weaker deceleration force,indicating that it may have been gradually stopped by the landslide dam formed during the October landslide.The sliding directions of the two landslides differed significantly in terms of both horizontal and vertical directions,indicating a change in their sliding surfaces.We conclude that unconsolidated materials at the top of the October landslide continued sliding along a curved slope during the November event.From our seismic models of dynamic processes,both the October landslide and local background may have affected and even changed a subsequent landslide’s mechanism.展开更多
The CO2reforming of CH4is studied over MgO‐promoted Ni catalysts,which were supported on alumina prepared from hydrotalcite.This presents an improved stability compared with non‐promoted catalysts.The introduction o...The CO2reforming of CH4is studied over MgO‐promoted Ni catalysts,which were supported on alumina prepared from hydrotalcite.This presents an improved stability compared with non‐promoted catalysts.The introduction of the MgO promoter was achieved through the‘‘memory effect’’of the Ni‐Al hydrotalcite structure,and ICP‐MS confirmed that only0.42wt.%of Mg2+ions were added into the Ni‐Mg/Al catalyst.Although no differences in the Ni particle size and basicity strength were observed,the Ni‐Mg/Al catalyst showed a higher catalytic stability than the Ni/Al catalyst.A series of surface reaction experiments were used and showed that the addition of a MgO promoter with low concentration can promote CO2dissociation to form active surface oxygen arising from the formation of the Ni‐MgO interface sites.Therefore,the carbon‐resistance promotion by nature was suggested to contribute to an oxidative environment around Ni particles,which would increase the conversion of carbon residues from CH4cracking to yield CO on the Ni metal surface.?2018,Dalian Institute of Chemical Physics,Chinese Academy of Sciences.Published by Elsevier B.V.All rights reserved.展开更多
Carbon deposition is sensitive to the metal particle sizes of supported Ni catalysts in CH_4/CO_2 reforming.To explore the reason of this phenomenon,Ni4,Ni8,and Ni12 which re flect the different cluster thicknesses su...Carbon deposition is sensitive to the metal particle sizes of supported Ni catalysts in CH_4/CO_2 reforming.To explore the reason of this phenomenon,Ni4,Ni8,and Ni12 which re flect the different cluster thicknesses supported on the MgO(100) slabs,have been employed to simulate Ni/MgO catalysts,and the reaction pathways of CH_4/CO_2 reforming on Nix/MgO(100) models are investigated by density functional theory.The reforming mechanisms of CH_4/CO_2 on different Nix/MgO(100) indicate the energy barriers of CH_4 dissociated adsorption,CH dissociation,and C oxidation three factors are all declining with the decrease of the Ni cluster sizes.The Hirshfeld charges analyses of three steps as described above show only Ni atoms in bottom two layers can obtain electrons from the MgO supporters,and the main electron transfer occurs between adsorbed species and their directly contacted Ni atoms.Due to more electron-rich Ni atoms in contact with the MgO supporters,the Ni/MgO catalysts with small Ni particles have a strong metal particle size effect and lead to its better catalytic activity.展开更多
Objective: To compare sexual function between primiparous women who underwent cesarean section (CS) and those who delivered vaginally. Methods: This cross-sectional study was conducted from October 2011 to April 2012 ...Objective: To compare sexual function between primiparous women who underwent cesarean section (CS) and those who delivered vaginally. Methods: This cross-sectional study was conducted from October 2011 to April 2012 in Beijing, China. The target population included women aged 18 - 45 years who had given birth only once at least 6 months prior. The questionnaire was self-administered including female sexual function measured using the Female Sexual Function Index (FSFI). Data were analyzed using R software with the significance level of 0.05. Results: A total of 1456 participants were included and 102 women (7.0%) declined. The median age of the participants was 35 years. The median time interval after childbirth was 6 years. The median FSFI score was 26.9 and prevalence of female sexual dysfunction (FSD) was 34.2%. Both the FSFI scores and the proportions of individuals with sexual disorders were similar between women undergoing CS and those having vaginal delivery for both individual domains and the full scale. Conclusion: There were insignificant differences in female sexual function scores and FSD prevalence between women undergoing CS versus vaginal delivery.展开更多
B-Lynch compression suturing was performed on a 30-year old primipara during emergency Cesarean section (CS). After CS, she developed a low-grade fever, a subinvolution and tenderness of the uterus, and a pronounced i...B-Lynch compression suturing was performed on a 30-year old primipara during emergency Cesarean section (CS). After CS, she developed a low-grade fever, a subinvolution and tenderness of the uterus, and a pronounced increase in the inflammatory markers. Antibiotics were altered according to bacterial cultures and drug sensitivity testing of the cervix. By 10 days postpartum, a diagnostic curettage was performed and released a foul-smelling liquid matter due to the substantial amount of heterogeneous material with gaseous echoes showed via ultrasonography. The inflammatory markers gradually returned to normal by 9 days post curettage. At 12-day post curettage, a foul-smelling purulent tissue was extruded spontaneously via the vagina and proved to be necrotic tissue on pathologic examination. Eighteen months after childbirth, the patient had not experienced a menstrual period or subsequent pregnancy and a small uterus without any evidence of an endometrium showed by ultrasonography.展开更多
Irrigation with reclaimed water is an important way to deal with water shortage of agricultural production and solve the problem of sewage pollution. The response of crop antioxidant enzyme system is an early-warning ...Irrigation with reclaimed water is an important way to deal with water shortage of agricultural production and solve the problem of sewage pollution. The response of crop antioxidant enzyme system is an early-warning indicator of environmental factors changes. Compared with raw wastewater and used fresh water as controls, this research studied peroxides （POD）, superoxide dismutase （SOD） activities and malondialdehyde （MDA） content in leaves from maize （Zea mays L.） and soybean （Phaseolus vulgaris L.） with pot culture under irrigating with reclaimed water which with secondary and third treatment. The results showed that secondary reclaimed water had some adverse effects on antioxidant system of maize in seedling stage, and the influence decreased in later stage of maize; effect of the third reclaimed water on antioxidant system of maize was not significant. Irrigation with reclaimed water has little influence on antioxidant system of soybean in seedling and reaping stage, but it could bring some oxidative stress in blossom stage. As a result, irrigating maize with second or third reclaimed water is safe to the growth of maize and soybean, but it is suggested that second reclaimed water should not be used in seedling stage of maize and reclaimed water should not be used in the second stage of soybean.展开更多
A co-precipitation method was employed to prepare Ni/Al_(2)O_(3)-ZrO_(2),Co/Al_(2)O_(3)-ZrO_(2)and Ni-Co/Al_(2)O_(3)-ZrO_(2)catalysts.Their properties were characterized by N_(2) adsorption(BET),thermogravimetric anal...A co-precipitation method was employed to prepare Ni/Al_(2)O_(3)-ZrO_(2),Co/Al_(2)O_(3)-ZrO_(2)and Ni-Co/Al_(2)O_(3)-ZrO_(2)catalysts.Their properties were characterized by N_(2) adsorption(BET),thermogravimetric analysis(TGA),temperature-programmed reduction(TPR),temperature-programmed desorption(CO_(2)-TPD),and temperature-programmed surface reaction(CH_(4)-TPSR and CO_(2)-TPSR).Ni-Co/Al_(2)O_(3)-ZrO_(2)bimetallic catalyst has good performance in the reduction of active components Ni,Co and CO_(2)adsorption.Compared with mono-metallic catalyst,bimetallic catalyst could provide more active sites and CO_(2)adsorption sites(C+CO_(2)=2CO)for the methane-reforming reaction,and a more appropriate force formed between active components and composite support(SMSI)for the catalytic reaction.According to the CH_(4)-CO_(2)-TPSR,there were 80.9%and 81.5%higher CH_(4) and CO_(2)conversion over Ni-Co/Al_(2)O_(3)-ZrO_(2)catalyst,and its better resistance to carbon deposition,less than 0.5%of coke after 4 h reaction,was found by TGA.The high activity and excellent anti-coking of the Ni-Co/Al_(2)O_(3)-ZrO_(2)catalyst were closely related to the synergy between Ni and Co active metal,the strong metal-support interaction and the use of composite support.展开更多
Tung tree(Vernicia fordii) is an economically important woody oil plant that produces tung oil rich in eleostearic acid. Here, we report a high-quality chromosome-scale genome sequence of tung tree. The genome sequenc...Tung tree(Vernicia fordii) is an economically important woody oil plant that produces tung oil rich in eleostearic acid. Here, we report a high-quality chromosome-scale genome sequence of tung tree. The genome sequence was assembled by combining Illumina short reads, Pacific Biosciences single-molecule real-time long reads, and Hi-C sequencing data. The size of tung tree genome is 1.12 Gb, with 28,422 predicted genes and over 73% repeat sequences. The V. fordii underwent an ancient genome triplication event shared by core eudicots but no further wholegenome duplication in the subsequent ca. 34.55 million years of evolutionary history of the tung tree lineage. Insertion time analysis revealed that repeat-driven genome expansion might have arisen as a result of long-standing long terminal repeat retrotransposon bursts and lack of efficient DNA deletion mechanisms. The genome harbors 88 resistance genes encoding nucleotide-binding sites;17 of these genes may be involved in early-infection stage of Fusarium wilt resistance. Further, 651 oil-related genes were identified, 88 of which are predicted to be directly involved in tung oil biosynthesis. Relatively few phosphoenolpyruvate carboxykinase genes, and synergistic effects between transcription factors and oil biosynthesis-related genes might contribute to the high oil content of tung seed. The tung tree genome constitutes a valuable resource for understanding genome evolution, as well as for molecular breeding and genetic improvements for oil production.展开更多
A phyllosphere bacterial strain EBL-06 was isolated from wheat leaves. The morphology, cultural characteristics, phospholipid fatty acids, physiological and antagonistic fungus activities of this strain were investiga...A phyllosphere bacterial strain EBL-06 was isolated from wheat leaves. The morphology, cultural characteristics, phospholipid fatty acids, physiological and antagonistic fungus activities of this strain were investigated. A phylogenetic tree was constructed by comparing with the published 16S rDNA sequences of the relevant bacteria. The results showed that the isolate EBL-06 was a strain of Paenibacillus polymyxa; this strain performed a high level of antagonistic fungus activity toward a broad spectrum of phytopathogens, such as Botrytis cinerea, Cladosporium cucumerinum, Fusarium spp. The isolate EBL-06 can grow well using monosodium glutamate wastewater （MGW） and potato wastewater （PW） as culture medium. The maximum yield of 6.5 × 10^9 CFU/mL of the isolate EBL-06 anti-fungus biocontrol agent was reached in 15 hr cultivation at 28℃, pH 6.0-7.5 using the mixture of MGW and PW （1：9）.展开更多
Flue gas from coal combustion contains significant amounts of volatile selenium （Se）. The capture of Se in the flue gas desulfurization （FGD） scrubber unit has resulted in a generation of metal-laden residues. It ...Flue gas from coal combustion contains significant amounts of volatile selenium （Se）. The capture of Se in the flue gas desulfurization （FGD） scrubber unit has resulted in a generation of metal-laden residues. It is important to determine Se speciation to understand the environmental impact of its disposal. A simple method has been developed for selective inorganic Se（IV）, Se（VI） and organic Se determination in the liquid-phase FGD residues by hydride generation atomic fluorescence spectrometry （AFS）. It has been determined that Se（IV）, Se（VI） and organic Se can be accurately determined with detection limits （DL） of 0.05, 0.06 and 0.06 μg/L, respectively. The accuracy of the proposed method was evaluated by analyzing the certified reference material, NIST CRM 1632c, and also by analyzing spiked tap-water samples. Analysis indicates that the concentration of Se is high in FGD liquid residues and primarily exists in a reduced state as selenite （Se（IV））. The toxicity of Se（IV） is the strongest of all Se species. Flue gas desulfurization residues pose a serious environmental risk.展开更多
The highway construction industry plays an important role in economic and development, but is also a primary source of carbon emission. Accordingly, with the global climate change, energy conservation and reduction of...The highway construction industry plays an important role in economic and development, but is also a primary source of carbon emission. Accordingly, with the global climate change, energy conservation and reduction of carbon emissions have become critical is- sues in the highway construction industry. However, to date, a model for the highway construction industry has not been established. Hence, to implement a low-carbon con- struction model for highways, this study divided asphalt pavement construction into aggregate stacking, aggregate supply, and other stages, and compiled a list of energy consumption investigation. An appropriate calculation model of CO2 emission was then built. Based on the carbon emission calculation model, the proportion of carbon emissions in each stage was analyzed. The analytic hierarchy process was used to establish the system of asphalt pavement construction with a judgment matrix, thereby enabling calculation of the weight coefficient of each link. In addition, the stages of aggregate heating, asphalt heating, and asphalt mixture mixing were defined as key stages of asphalt pavement construction. Carbon emissions at these stages accounted for approximately 90% of the total carbon emissions. Carbon emissions at each stage and their impact on the environment were quantified and compared. The energy saving construction schemes as well as the environmental and socioeconomic benefits were then proposed. Through these schemes, significant reductions in carbon emissions and costs can be achieved. The results indicate that carbon emissions reduce by 32.30% and 35.93%, whereas costs reduce by 18.58% and 6.03%. The proposed energy-saving and emission reduction scheme can pro- vide a theoretical basis and technical support for the development of low-carbon highway construction.展开更多
Foxtail millet is one of the earliest domesticated cereal crops in the world.Its domestication has been traced back to the early Holocene(10,000–8000 cal a BP),first appearing in the basins of the Yellow River and We...Foxtail millet is one of the earliest domesticated cereal crops in the world.Its domestication has been traced back to the early Holocene(10,000–8000 cal a BP),first appearing in the basins of the Yellow River and Western Liao River[1].Dryland farming dominated by foxtail millet was ultimately established in the Central Plains during the middle Holocene(6000–5500 cal a BP)[2].This agricultural system served as the vital subsistence basis for demographic growth,a rise in urbanization,and the formation and continuous development of Chinese civilization.This cereal had traditionally been a major and valuable staple-food crop in northern China.In the late Holocene,along with human migration and innovative agricultural technology communication,foxtail millet cultivation expanded outward on a large scale and to a wide range of new habitats far away from its original center of domestication[3].展开更多
基金the financial support from the National Key Research and Development Program of China(2022YFB4101302-01)the National Natural Science Foundation of China(22178243)the science and technology innovation project of China Shenhua Coal to Liquid and Chemical Company Limited(MZYHG-22–02).
文摘The cyclic hydrogenation technology in a direct coal liquefaction process relies on the dissolved hydrogen of the solvent or oil participating in the hydrogenation reaction.Thus,a theoretical basis for process optimization and reactor design can be established by analyzing the solubility of hydrogen in liquefaction solvents.Experimental studies of hydrogen solubility in liquefaction solvents are challenging due to harsh reaction conditions and complex solvent compositions.In this study,the composition and content of liquefied solvents were analyzed.As model compounds,hexadecane,toluene,naphthalene,tetrahydronaphthalene,and phenanthrene were chosen to represent the liquefied solvents in chain alkanes and monocyclic,bicyclic,and tricyclic aromatic hydrocarbons.The solubility of hydrogen X(mol/mol)in pure solvent components and mixed solvents(alkanes and aromatics mixed in proportion to the chain alkanes+bicyclic aromatic hydrocarbons,bicyclic saturated aromatic hydrocarbons+bicyclic aromatic hydrocarbons,and bicyclic aromatic hydrocarbons+compounds containing het-eroatoms composed of mixed components)are determined using Aspen simulation at temperature and pressure conditions of 373–523 K and 2–10 MPa.The results demonstrated that at high temperatures and pressures,the solubility of hydrogen in the solvent increases with the increase in temperature and pressure,with the pressure having a greater impact.Further-more,the results revealed that hydrogen is more soluble in straight-chain alkanes than in other solvents,and the solubility of eicosanoids reaches a maximum of 0.296.The hydrogen solubility in aromatic ring compounds decreased gradually with an increase in the aromatic ring number.The influence of chain alkanes on the solubility of hydrogen predominates in a mixture of solvents with different mixing ratios of chain alkanes and aromatic hydrocarbons.The solubility of hydrogen in mixed aromatic solvents is less than that in the corresponding single solvents.Hydrogen is less soluble in solvent compounds containing heteroatoms than in compounds without heteroatoms.
基金Supported by National Natural Science Foundation of China (Grant No.U21A20122)Zhejiang Provincial Natural Science Foundation of China (Grant No.LY22E050012)+2 种基金China Postdoctoral Science Foundation (Grant Nos.2023T160580,2023M743102)Open Foundation of the State Key Laboratory of Fluid Power and Mechatronic Systems of China (Grant No.GZKF-202225)Students in Zhejiang Province Science and Technology Innovation Plan of China (Grant No.2023R403073)。
文摘Fine particulate matter produced during the rapid industrialization over the past decades can cause significant harm to human health.Twin-fluid atomization technology is an effective means of controlling fine particulate matter pollution.In this paper,the influences of the main parameters on the droplet size,effective atomization range and sound pressure level(SPL)of a twin-fluid nozzle(TFN)are investigated,and in order to improve the atomization performance,a multi-objective synergetic optimization algorithm is presented.A multi-physics coupled acousticmechanics model based on the discrete phase model(DPM),large eddy simulation(LES)model,and Ffowcs Williams-Hawkings(FW-H)model is established,and the numerical simulation results of the multi-physics coupled acoustic-mechanics method are verified via experimental comparison.Based on the analysis of the multi-physics coupled acoustic-mechanics numerical simulation results,the effects of the water flow on the characteristics of the atomization flow distribution were obtained.A multi-physics coupled acoustic-mechanics numerical simulation result was employed to establish an orthogonal test database,and a multi-objective synergetic optimization algorithm was adopted to optimize the key parameters of the TFN.The optimal parameters are as follows:A gas flow of 0.94 m^(3)/h,water flow of 0.0237 m^(3)/h,orifice diameter of the self-excited vibrating cavity(SVC)of 1.19 mm,SVC orifice depth of 0.53 mm,distance between SVC and the outlet of nozzle of 5.11 mm,and a nozzle outlet diameter of 3.15 mm.The droplet particle size in the atomization flow field was significantly reduced,the spray distance improved by 71.56%,and the SPL data at each corresponding measurement point decreased by an average of 38.96%.The conclusions of this study offer a references for future TFN research.
基金support from the National Natural Science Foundation of China(22038008)the science and technology innovation project of China Shenhua Coal to Liquid and Chemical Company Limited(MZYHG-2021-01).
文摘Focusing on the use of imidazolium ionic liquids and quaternary ammonium salts-based deep eutectic solvents for the separation of phenols and nitrogen-containing heteroaromatics,the role of heteroaromatics as specific sites for hydrogen bond-based separation has been investigated.These environmentally friendly solvents are known for their ability to form hydrogen bonds with heteroatoms,a key aspect in separation processes.We quantified the hydrogen bond interaction energy to reach the threshold energy for efficient O-and N-heteroaromatics separation.This article provides an in-depth study of the structural nuances of different hydrogen bonding sites and their affinity properties while conducting a comparative evaluation of the separation efficiency of ionic liquids and deep eutectic solvents from a thermodynamic perspective.Results showed that phenols with dual hydrogen bonding recognition sites were easier to separate than nitrogen-containing heteroaromatics.Imidazolium ionic liquids were more suitable for the extraction of nonbasic nitrogen-containing heteroaromatics,and quaternary ammonium salts-based deep eutectic solvents are more effective for phenols and basic nitrogen-containing heteroaromatics,which was confirmed by Fourier transform infrared spectroscopy and empirical tests.Therefore,this study provides a theoretical basis for the strategy design and selection of extractants for the efficient separation of O-and N-containing aromatic compounds.
基金supported by the National Natural Science Foundation of China (Grant No.32171843)the Postgraduate Scientific Research Innovation Project of Hunan Province (Grant No.CX20200696)the Scientific Innovation Fund for Graduate of Central South University of Forestry and Technology (Grant No.CX20201003)。
文摘The mu oil tree(Vernicia montana Lour.) is a dioecious species, but the genetic mechanisms underlying its phenotypic sexual dimorphism are unclear. In this study, we determined two pivotal phases of sex differentiation of mu oil tree via morphological and histological analyses of unisexual flowers:(Ⅰ) differentiation of male or female primordia to produce staminate flowers(SFs) or transient hermaphrodite flowers(HFs),and(Ⅱ) complete abortion of stamens in transient HFs to generate pistillate flowers(PFs). A total of 1621 sex-biased genes were identified by comparative transcriptome analysis which exhibited elevated rates of protein evolution than unbiased genes. The female-biased genes were enriched in the production of defense compounds while male-biased genes were focused on the production of viable pollens. Transcriptomebased analysis revealed that the differentially expressed genes(DEGs) between PFs and SFs in phase Ⅰ involved in abscisic acid(ABA), auxin(AUX), cytokinin(CK), ethylene(ET), and gibberellin(GA) biosynthesis and signaling showed higher expression levels in males than in females in general, whereas the DEGs involved in jasmonic acid(JA) and salicylic acid(SA) pathways displayed opposite expression patterns. Moreover,differentially expressed endogenous ABA, AUX, GAs, JA, and SA exhibited consistent biased expression patterns with the DEGs by UPLC-MSbased analysis. Exogenous application of an anti-ethylene plant growth regulator could promote the development of stamens in PFs and generated HFs. Comparative transcriptomic and hormonal analyses of PFs and SFs in phase Ⅱ indicated an increase in ET concentration when abortion of stamens in PFs occurred. This study suggested that phytohormones play key roles in sex dimorphism and ET may determine the development of stamens in PFs of mu oil tree, which provides an insight into plant sex differentiation mechanisms.
基金the Bureau of Disease Control,National Health and Family Planning Commission of the People’s Republic of China for their support
文摘Objective：To analyze the incidence and mortality rates of laryngeal cancer in China from 2008 to 2012.Methods：Incident and death cases of laryngeal cancer were retrieved from the National Central Cancer Registry（NCCR）database collecting from 135 cancer registries in China during 2008–2012.The crude incidence and mortality rates of laryngeal cancer were calculated by area（urban/rural）,region（eastern,middle,western）,gender and age group（0,1–4,5–9,…,85＋）.China census in 2000 and Segi’s world population were applied for age standardized rates.Join Point（Version 4.5.0.1）model was used for time trend analysis.Results：The crude incidence rate of laryngeal cancer was 1.86/100,000 ranked the 21st in overall cancers.The age-standardized incidence rates by China population（ASIRC）and by World population（ASIRW）were1.22/100,000 and 1.23/100,000,respectively.The crude mortality of laryngeal cancer in China was 1.01/100,000and it was the 21st cause of cancer-related death in overall cancers.Both the age-standardized mortality rates by Chinese standard population（ASMRC）and by world standard population（ASMRW）were 0.63/100,000.Incidence and mortality rates of laryngeal cancer were higher in males than in females and higher in urban areas than in rural areas.Middle areas had the highest incidence and mortality rates followed by eastern and western areas.Incidence and mortality rates of laryngeal cancer retained low level before age of 40 years old but increased greatly after and peaked in age group of 75.Incidence showed significant down trends in recent 10 years by 1.27%annually[95%confidence interval（95%CI）：–2.2%,–0.3%].Mortality declined in females sharply by 5.18%per year although stable in males and both sexes combined.Conclusions：Appropriate targeted prevention,early detection and treatment programs should be carried out to control the local burden of laryngeal cancer.
基金This work was supported by the National Natural Science Foundation of China(Nos.42074058,41822401,and 42021003)the National Key Research and Development Program of China(No.2018YFC1503705).
文摘Two large landslides successively blocked the Jinsha River at the same location in Jiangda Village on October 10 and November 3,2018,respectively.The dynamic processes and possible interactions of the two landslides need to be studied to better understand the physical processes involved,and to provide information on future disaster mitigation.We investigated their force histories and sliding directions by inverting regional broadband seismograms.The scale of the October landslide was approximately three times that of the November event.The October event revealed a particularly strong deceleration force,which may have been caused by a collision between the sliding mass and ground surface.In contrast,the November event had a relatively weaker deceleration force,indicating that it may have been gradually stopped by the landslide dam formed during the October landslide.The sliding directions of the two landslides differed significantly in terms of both horizontal and vertical directions,indicating a change in their sliding surfaces.We conclude that unconsolidated materials at the top of the October landslide continued sliding along a curved slope during the November event.From our seismic models of dynamic processes,both the October landslide and local background may have affected and even changed a subsequent landslide’s mechanism.
基金supported by the National Natural Science Fundation of China(U1361202,51276120)~~
文摘The CO2reforming of CH4is studied over MgO‐promoted Ni catalysts,which were supported on alumina prepared from hydrotalcite.This presents an improved stability compared with non‐promoted catalysts.The introduction of the MgO promoter was achieved through the‘‘memory effect’’of the Ni‐Al hydrotalcite structure,and ICP‐MS confirmed that only0.42wt.%of Mg2+ions were added into the Ni‐Mg/Al catalyst.Although no differences in the Ni particle size and basicity strength were observed,the Ni‐Mg/Al catalyst showed a higher catalytic stability than the Ni/Al catalyst.A series of surface reaction experiments were used and showed that the addition of a MgO promoter with low concentration can promote CO2dissociation to form active surface oxygen arising from the formation of the Ni‐MgO interface sites.Therefore,the carbon‐resistance promotion by nature was suggested to contribute to an oxidative environment around Ni particles,which would increase the conversion of carbon residues from CH4cracking to yield CO on the Ni metal surface.?2018,Dalian Institute of Chemical Physics,Chinese Academy of Sciences.Published by Elsevier B.V.All rights reserved.
基金Supported by the National Natural Science Foundation of China(U1361202,51276120)
文摘Carbon deposition is sensitive to the metal particle sizes of supported Ni catalysts in CH_4/CO_2 reforming.To explore the reason of this phenomenon,Ni4,Ni8,and Ni12 which re flect the different cluster thicknesses supported on the MgO(100) slabs,have been employed to simulate Ni/MgO catalysts,and the reaction pathways of CH_4/CO_2 reforming on Nix/MgO(100) models are investigated by density functional theory.The reforming mechanisms of CH_4/CO_2 on different Nix/MgO(100) indicate the energy barriers of CH_4 dissociated adsorption,CH dissociation,and C oxidation three factors are all declining with the decrease of the Ni cluster sizes.The Hirshfeld charges analyses of three steps as described above show only Ni atoms in bottom two layers can obtain electrons from the MgO supporters,and the main electron transfer occurs between adsorbed species and their directly contacted Ni atoms.Due to more electron-rich Ni atoms in contact with the MgO supporters,the Ni/MgO catalysts with small Ni particles have a strong metal particle size effect and lead to its better catalytic activity.
文摘Objective: To compare sexual function between primiparous women who underwent cesarean section (CS) and those who delivered vaginally. Methods: This cross-sectional study was conducted from October 2011 to April 2012 in Beijing, China. The target population included women aged 18 - 45 years who had given birth only once at least 6 months prior. The questionnaire was self-administered including female sexual function measured using the Female Sexual Function Index (FSFI). Data were analyzed using R software with the significance level of 0.05. Results: A total of 1456 participants were included and 102 women (7.0%) declined. The median age of the participants was 35 years. The median time interval after childbirth was 6 years. The median FSFI score was 26.9 and prevalence of female sexual dysfunction (FSD) was 34.2%. Both the FSFI scores and the proportions of individuals with sexual disorders were similar between women undergoing CS and those having vaginal delivery for both individual domains and the full scale. Conclusion: There were insignificant differences in female sexual function scores and FSD prevalence between women undergoing CS versus vaginal delivery.
文摘B-Lynch compression suturing was performed on a 30-year old primipara during emergency Cesarean section (CS). After CS, she developed a low-grade fever, a subinvolution and tenderness of the uterus, and a pronounced increase in the inflammatory markers. Antibiotics were altered according to bacterial cultures and drug sensitivity testing of the cervix. By 10 days postpartum, a diagnostic curettage was performed and released a foul-smelling liquid matter due to the substantial amount of heterogeneous material with gaseous echoes showed via ultrasonography. The inflammatory markers gradually returned to normal by 9 days post curettage. At 12-day post curettage, a foul-smelling purulent tissue was extruded spontaneously via the vagina and proved to be necrotic tissue on pathologic examination. Eighteen months after childbirth, the patient had not experienced a menstrual period or subsequent pregnancy and a small uterus without any evidence of an endometrium showed by ultrasonography.
基金This paper was supported by the National High Technology Research and Development Program of China （863 Program, No. 2006AA100205） and National Natural Science Foundation of China （No. 50679080）
文摘Irrigation with reclaimed water is an important way to deal with water shortage of agricultural production and solve the problem of sewage pollution. The response of crop antioxidant enzyme system is an early-warning indicator of environmental factors changes. Compared with raw wastewater and used fresh water as controls, this research studied peroxides （POD）, superoxide dismutase （SOD） activities and malondialdehyde （MDA） content in leaves from maize （Zea mays L.） and soybean （Phaseolus vulgaris L.） with pot culture under irrigating with reclaimed water which with secondary and third treatment. The results showed that secondary reclaimed water had some adverse effects on antioxidant system of maize in seedling stage, and the influence decreased in later stage of maize; effect of the third reclaimed water on antioxidant system of maize was not significant. Irrigation with reclaimed water has little influence on antioxidant system of soybean in seedling and reaping stage, but it could bring some oxidative stress in blossom stage. As a result, irrigating maize with second or third reclaimed water is safe to the growth of maize and soybean, but it is suggested that second reclaimed water should not be used in seedling stage of maize and reclaimed water should not be used in the second stage of soybean.
基金supported by the National Basic Research Program of China(2005CB221207)the National Natural Science Foundation of China(Grants Nos.20846002,U0970134)+2 种基金the Program for Changjiang Scholars and Innovative Research Team in University(No.IRT0517)the Program for New Century Excellent Talents in University(No.NCET-05-0267)the Ph.D.Programs Foundation for New Teacher(No.20091402120013)in Ministry of Education,China。
文摘A co-precipitation method was employed to prepare Ni/Al_(2)O_(3)-ZrO_(2),Co/Al_(2)O_(3)-ZrO_(2)and Ni-Co/Al_(2)O_(3)-ZrO_(2)catalysts.Their properties were characterized by N_(2) adsorption(BET),thermogravimetric analysis(TGA),temperature-programmed reduction(TPR),temperature-programmed desorption(CO_(2)-TPD),and temperature-programmed surface reaction(CH_(4)-TPSR and CO_(2)-TPSR).Ni-Co/Al_(2)O_(3)-ZrO_(2)bimetallic catalyst has good performance in the reduction of active components Ni,Co and CO_(2)adsorption.Compared with mono-metallic catalyst,bimetallic catalyst could provide more active sites and CO_(2)adsorption sites(C+CO_(2)=2CO)for the methane-reforming reaction,and a more appropriate force formed between active components and composite support(SMSI)for the catalytic reaction.According to the CH_(4)-CO_(2)-TPSR,there were 80.9%and 81.5%higher CH_(4) and CO_(2)conversion over Ni-Co/Al_(2)O_(3)-ZrO_(2)catalyst,and its better resistance to carbon deposition,less than 0.5%of coke after 4 h reaction,was found by TGA.The high activity and excellent anti-coking of the Ni-Co/Al_(2)O_(3)-ZrO_(2)catalyst were closely related to the synergy between Ni and Co active metal,the strong metal-support interaction and the use of composite support.
基金supported by the National Key R&D Program of China(Grant No.2017YFD0600703)the National Forestry Public Welfare Industry Research Project of China(Grant No.201204403)+2 种基金the Outstanding Youth Project of the Education Department of Hunan Province,China(Grant No.17B279)the US Department of AgricultureAgricultural Research Service(USDA-ARS)National Program for Quality and Utilization of Agricultural Products(NP 306Grant No.CRIS 6054-41000-103-00-D).
文摘Tung tree(Vernicia fordii) is an economically important woody oil plant that produces tung oil rich in eleostearic acid. Here, we report a high-quality chromosome-scale genome sequence of tung tree. The genome sequence was assembled by combining Illumina short reads, Pacific Biosciences single-molecule real-time long reads, and Hi-C sequencing data. The size of tung tree genome is 1.12 Gb, with 28,422 predicted genes and over 73% repeat sequences. The V. fordii underwent an ancient genome triplication event shared by core eudicots but no further wholegenome duplication in the subsequent ca. 34.55 million years of evolutionary history of the tung tree lineage. Insertion time analysis revealed that repeat-driven genome expansion might have arisen as a result of long-standing long terminal repeat retrotransposon bursts and lack of efficient DNA deletion mechanisms. The genome harbors 88 resistance genes encoding nucleotide-binding sites;17 of these genes may be involved in early-infection stage of Fusarium wilt resistance. Further, 651 oil-related genes were identified, 88 of which are predicted to be directly involved in tung oil biosynthesis. Relatively few phosphoenolpyruvate carboxykinase genes, and synergistic effects between transcription factors and oil biosynthesis-related genes might contribute to the high oil content of tung seed. The tung tree genome constitutes a valuable resource for understanding genome evolution, as well as for molecular breeding and genetic improvements for oil production.
基金supported by the National Natural Science Foundation of China (No. 30600082)the Knowledge Innovation Program of Chinese Academy of Sciences (No.KSCX2-YW-G-054-2)the Key Technologies R&D Program of China (No. 2008BADA7B01)
文摘A phyllosphere bacterial strain EBL-06 was isolated from wheat leaves. The morphology, cultural characteristics, phospholipid fatty acids, physiological and antagonistic fungus activities of this strain were investigated. A phylogenetic tree was constructed by comparing with the published 16S rDNA sequences of the relevant bacteria. The results showed that the isolate EBL-06 was a strain of Paenibacillus polymyxa; this strain performed a high level of antagonistic fungus activity toward a broad spectrum of phytopathogens, such as Botrytis cinerea, Cladosporium cucumerinum, Fusarium spp. The isolate EBL-06 can grow well using monosodium glutamate wastewater （MGW） and potato wastewater （PW） as culture medium. The maximum yield of 6.5 × 10^9 CFU/mL of the isolate EBL-06 anti-fungus biocontrol agent was reached in 15 hr cultivation at 28℃, pH 6.0-7.5 using the mixture of MGW and PW （1：9）.
基金supported by the National Natural Science Foundation of China (No.90410018)the Shanxi Nature Science Foundation (No.20051017)+1 种基金the Shanxi Returned Scholar Research Project (No.2005-21)the Programfor Changjiang Scholars and Innovative Research Team at University in MOE,China (No.IRT0517)
文摘Flue gas from coal combustion contains significant amounts of volatile selenium （Se）. The capture of Se in the flue gas desulfurization （FGD） scrubber unit has resulted in a generation of metal-laden residues. It is important to determine Se speciation to understand the environmental impact of its disposal. A simple method has been developed for selective inorganic Se（IV）, Se（VI） and organic Se determination in the liquid-phase FGD residues by hydride generation atomic fluorescence spectrometry （AFS）. It has been determined that Se（IV）, Se（VI） and organic Se can be accurately determined with detection limits （DL） of 0.05, 0.06 and 0.06 μg/L, respectively. The accuracy of the proposed method was evaluated by analyzing the certified reference material, NIST CRM 1632c, and also by analyzing spiked tap-water samples. Analysis indicates that the concentration of Se is high in FGD liquid residues and primarily exists in a reduced state as selenite （Se（IV））. The toxicity of Se（IV） is the strongest of all Se species. Flue gas desulfurization residues pose a serious environmental risk.
基金supported by Natural Science Foundation of Shaanxi Province (2011JM7001)Communications Scientific Research Project of Gansu Province (201227)
文摘The highway construction industry plays an important role in economic and development, but is also a primary source of carbon emission. Accordingly, with the global climate change, energy conservation and reduction of carbon emissions have become critical is- sues in the highway construction industry. However, to date, a model for the highway construction industry has not been established. Hence, to implement a low-carbon con- struction model for highways, this study divided asphalt pavement construction into aggregate stacking, aggregate supply, and other stages, and compiled a list of energy consumption investigation. An appropriate calculation model of CO2 emission was then built. Based on the carbon emission calculation model, the proportion of carbon emissions in each stage was analyzed. The analytic hierarchy process was used to establish the system of asphalt pavement construction with a judgment matrix, thereby enabling calculation of the weight coefficient of each link. In addition, the stages of aggregate heating, asphalt heating, and asphalt mixture mixing were defined as key stages of asphalt pavement construction. Carbon emissions at these stages accounted for approximately 90% of the total carbon emissions. Carbon emissions at each stage and their impact on the environment were quantified and compared. The energy saving construction schemes as well as the environmental and socioeconomic benefits were then proposed. Through these schemes, significant reductions in carbon emissions and costs can be achieved. The results indicate that carbon emissions reduce by 32.30% and 35.93%, whereas costs reduce by 18.58% and 6.03%. The proposed energy-saving and emission reduction scheme can pro- vide a theoretical basis and technical support for the development of low-carbon highway construction.
基金supported by the National Natural Science Foundation of China(41907369 and 41672171)Chinese Academy of Sciences(CAS)Project for Young Scientists in Basic Research(YSBR-019)+1 种基金the Fundamental Research Funds for the Central Universities(E0E48931X2)Chongqing Normal University Fund(21XWB031)。
文摘Foxtail millet is one of the earliest domesticated cereal crops in the world.Its domestication has been traced back to the early Holocene(10,000–8000 cal a BP),first appearing in the basins of the Yellow River and Western Liao River[1].Dryland farming dominated by foxtail millet was ultimately established in the Central Plains during the middle Holocene(6000–5500 cal a BP)[2].This agricultural system served as the vital subsistence basis for demographic growth,a rise in urbanization,and the formation and continuous development of Chinese civilization.This cereal had traditionally been a major and valuable staple-food crop in northern China.In the late Holocene,along with human migration and innovative agricultural technology communication,foxtail millet cultivation expanded outward on a large scale and to a wide range of new habitats far away from its original center of domestication[3].
