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Modelling plant canopy effects on water-heat exchange in the freezingthawing processes of active layer on the Qinghai-Tibet Plateau

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Journal of Mountain Science 2021年第6期18卷 1564-1579页

作者： GUO Lin-mao chang juan XU Hong-liang SUN Wen-jun Key Laboratory of Western China's Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610000China

The effect of vegetation on the water-heat exchange in the freezing-thawing processes of active layer is one of the key issues in the study of land surface processes and in predicting the response of alpine ecosystems to climate change in permafrost regions. In this study, we used the simultaneous heat and water model to investigate the effects of plant canopy on surface and subsurface hydrothermal dynamics in the Fenghuoshan area of the QinghaiTibet Plateau by changing the leaf area index(LAI) and keeping other variables constant. Results showed that the sensible heat, latent heat and net radiation are increased with an increase in the LAI. However, the ground heat flux decreased with an increasing LAI. The annual total evapotranspiration and vegetation transpiration ranged from-16% to 9% and-100% to 15%, respectively, in response to extremes of doubled and zero LAI, respectively. There was a negative feedback between vegetation and the volumetric unfrozen water content at 0.2 m through changing evapotranspiration. The simulation results of soil temperature and moisture suggest that better vegetation conditions are conducive to maintaining the thermal stability of the underlying permafrost, and the advanced initial thawing time and increasing thawing rate of soil ice with the increase in the LAI may have a great influence on the timing and magnitude of supra-permafrost groundwater. This study quantifies the impact of vegetation change on surface and subsurface hydrothermal processes and provides a basic understanding for evaluating the impact of vegetation degradation on the water-heat exchange in permafrost regions under climate change.

关键词： Permafrost Simultaneous heat and water model Leaf area index Water-Heat exchange Thermal-moisture dynamics

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Research on hydration of phenylacetylene assisted with additives in near-critical water

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Chinese Chemical Letters 2011年第4期22卷 393-396页

作者： Shuang Li Yong juan chang Yu Wang Li Yi Dai Shanghai Key Laboratory of Green Chemistry and Chemical Process Department of Chemistry East China Normal UniversityShanghai 200062China

The hydration of phenylacetylene in near-critical water,assisted with additives（NaHSO4,ZnCl2,FeCl3）,has been successfully conducted with temperature and residence time ranges of 220-300℃and 60-180 min,*** results showed the catalytic ability is *** maximum yield of product acetophenone was 96.68%at 260℃,120 *** on the results found,a possible mechanism of hydration of phenylacetylene in near-critical water was proposed.

关键词： Hydration Phenylacetylene Additives Near-critical water Mechanism

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Research on Mediate Temperature Decomposition of High Nitrogen Austenite

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材料热处理学报 2004年第5期25卷 214-216页

作者： LIXiao-ling BEIDuo-hui HUMing-juan ZHUZu-chang SchoolofMaterialScienceandEngineering ShanghaiJiaoTongUniversityShanghaiChina

The decomposed products from high nitrogen austenite aging at 225°C were investigated by TEM. It is found that the shape of decomposition products inside the austenite grains is not regular and not strictly oriented. Preferential nucleation of y-Fe4N at dislocations and grain boundaries has been observed. It also has been found that during the first stage of the high nitrogen austenite decomposition a large quantity of ultra-fine /-Fe4N precipitate inside the parent austenite, which has been thought to be the undecomposed region before. The ultimate products are composed of highly dispersed a-Fe and /-Fe4N, with both of them maintaining nanometer scale. The micro-hardness of them can be as high as 900HV.

关键词：高氮奥氏体温度分解微硬度 TEM

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Seasonal dynamics of suprapermafrost groundwater and its response to the freeing-thawing processes of soil in the permafrost region of Qinghai-Tibet Plateau

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Science China Earth Sciences 2015年第4期58卷 727-738页

作者： chang juan WANG GenXu LI ChunJie MAO TianXu College of Earth and Environment Science Lanzhou University Institute of Mountain Hazards and Environment Chinese Academy of Sciences

The suprapermafrost groundwater in permafrost region not only is an important component of the water cycle and land surface process, but also is closely associated with the charges of ecological environment in cold region. However, the seasonal dynamics, driving factors, and mechanism of suprapermafrost groundwater are not well understood. Based on observation at slope scale on suprapermafrost groundwater dynamics of typical alpine meadows in the Qinghai-Tibet Plateau, the seasonal dynamics, spatial distribution and driving factors of suprapermafrost groundwater were analyzed. The results showed that there were close relationships between the seasonal dynamics of suprapermafrost groundwater and the freezing-thawing processes of active soil in permafrost region. The seasonal dynamics of suprapermafrost groundwater and its slope distribution pattern were controlled by soil temperature of active layers. The phase and range of the suprapermafrost groundwater dynamics are determined by deep soil(below 60 cm depth) moisture and groundwater recharging sources. The relationship between active soil temperatures and dynamics of suprapermafrost groundwater levels was better described by Boltzmann functions. However, the influencing thresholds of soil temperature on groundwater dynamics varied at different depths of active layers and in different slope positions, which resulted in the significant spatial heterogeneity of suprapermafrost groundwater dynamics in slope scale. Land cover change and global warming certainly altered the dynamics of suprapermafrost groundwater and the hydraulic interaction between groundwater and rivers, and consequently altered the overall hydrologic cycle of watershed scale.

关键词： suprapermafrost groundwater seasonal dynamics soil hydrothermal characteristics freezing-thawing process

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Interleukin-4 promotes microglial polarization toward a neuroprotective phenotype after retinal ischemia/reperfusion injury

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Neural Regeneration Research 2022年第12期17卷 2755-2760页

作者： Di Chen Cheng Peng Xu-Ming Ding Yue Wu chang-juan Zeng Li Xu Wen-Yi Guo Department of Ophthalmology Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghaiChina Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology ShanghaiChina

Glaucoma results from irreversible loss of retinal ganglion cells(RGCs)through an unclear *** polarization and neuroinflammation play an important role in retinal *** study aimed to explore the function of microglial polarization during glaucoma progression and identify a strategy to alleviate retinal *** ischemia/reperfusion injury was induced in C57BL/6 *** a separate cohort of animals,interleukin(IL)-4(50 ng/mL,2μL per injection)or vehicle was intravitreally injected after retinal ischemia/reperfusion *** loss was assessed by counting cells that were positive for the RGC marker RNA binding protein,mRNA processing factor in retinal flat *** expression of classically activated(M1)and alternatively activated(M2)microglial markers were assessed by quantitative reverse transcription-polymerase chain reaction,immunofluorescence,and western *** results showed that progressive RGC loss was accompanied by a continuous decrease in M2 microglia during the late phase of the 28-day period after retinal ischemia/reperfusion ***-4 was undetectable in the retina at all time points,and intravitreal IL-4 administration markedly improved M2 microglial marker expression and ameliorated RGC loss in the late phase post-retinal ischemia/reperfusion *** summary,we observed that IL-4 treatment maintained a high number of M2 microglia after RIR and promoted RGC survival.

关键词： glaucoma hyper-intraocular pressure in vivo interleukin-4 intravitreal injection M2 microglia neurodegeneration neuroprotective effect retinal ganglion cell retinal ischemia-reperfusion

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Fermented soybean meal improves the growth performance, nutrient digestibility, and microbial flora in piglets

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Animal Nutrition 2017年第1期3卷 19-24页

作者： Lin Yuan juan chang Qingqiang Yin Min Lu Yuanran Di Ping Wang Zhixiang Wang Erzhu Wang Fushan Lu College of Animal Science and Veterinary Medicine Henan Agricultural University Institute of Animal Husbandry and Veterinary Medicine Henan Academy of Agricultural Sciences Henan Delin Biological Product Co.Ltd. Henan Engineering and Technology Research Center of Feed Microbes

In order to increase nutritive values of soybean meal(SBM), 3 species of microbes were used to ferment SBM. Through a 3 x 3 orthogonal design and parameter measurements of soybean peptide and antinutritional factor contents in the fermented soybean meal(FSBM), it was estimated that the best microbial proportion of Bacillus subtilis, Hansenula anomala and Lactobacillus casei was 2:1:2 for SBM fermentation(P 0.05). However, newlyweaned piglets(d 28-38) fed 10% FSBM and different levels of plasma protein obtained higher average daily gain(ADG) and feed conversion ratio(FCR), compared with those without FSBM but with 6% plasma protein(P < 0.05). Piglets(d 38-68) fed diets supplemented with FSBM and soybean protein concentrate(SBPC) at 3.75% and 7.5% respectively increased nutrient digestibility,fecal enzyme activity and lactic acid bacteria counts, and decreased fecal Escherichia coli counts(P < 0.05), compared with the control. These data indicated that FSBM had positive effects on nutrient digestibility and fecal microflora for piglets.

关键词： Fermented soybean meal Combined microbes Growth performance Nutrient digestibility Piglets

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Syntheses and Crystal Structures of Bis-[oxo-bis(p-ferrocenylbenzoxy di-n-propyltin)](I) and Bis[oxo-bis(β-ferrocenoylpropionyloxy di-n-propyltin )](II)

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Chinese Journal of Structural Chemistry 2003年第6期22卷 647-652页

作者： PENG Bin SUN Li-juan chang Wei-Xing XIE Qing-Lan② (National Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, China) National Key Laboratory of Elemento-Organic Chemistry Nankai University

Bis-[oxo-bis(p-ferrocenylbenzoxy di-n-propyltin)] I and bis-[oxo-bis(-ferrocenoyl- propionyloxy di-n-propyltin)] II were synthesized and their crystal structures have been determined by X-ray diffraction analysis. The compound I2C6H6 ([(FcC6H4COOSnPr2)2O]22C6H6 or C92H108Fe4O10Sn42C6H6, Mr = 2384.16) is of triclinic, space group P?with a = 12.826(4), b = 13.099(5), c = 17.539(5) ? = 78.229(5), ?= 71.852(5), = 62.746(5)? V = 2483(1) ?, Z = 1, Dc = 1.490 g/cm3, = 0.71073 ? (MoK? =1.611 mm-1 and F(000) = 1128. The structure was refined to R = 0.0491 and wR = 0.1053 for 4690 unique reflections with I > 2(I). The compound IIC6H6 ([(FcCOCH2CH2COOSnPr2)2O]2C6H6 or C80H108Fe4O14Sn4C6H6, Mr = 2115.93) is of triclinic, space group P?with a = 11.260(4), b = 14.126(5), c = 15.961(6) ? = 91.400(6), = 110.654(6), = 104.931(6), V = 2277(1) 3, Z = 1, Dc = 1.510 g/cm3, = 0.71073 ? (MoK? = 1.750 mm-1 and F(000) = 1046. The structure was refined to R = 0.0466 and wR = 0.1138 for 5061 unique reflections with I > 2(I). The two compounds have the similar structures: both are dimers containing centrosymmetric Sn2O2 cores. But there are some differences in the ligating modes between the carboxylate groups and the Sn atoms.

关键词： ferrocenecarboxylate diorganotin dimers X-ray diffraction

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Generation and Immunogenicity of a Recombinant Adenovirus Co-Expressing the E2 Protein of Classical Swine Fever Virus and the GP5 Protein of Porcine Reproduction and Respiratory Syndrome Virus

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Agricultural Sciences in China 2011年第11期10卷 1781-1791页

作者： LI Hong-yun SUN Yuan ZHANG Xing-juan chang Tian-ming WANG Xiang-peng HE Fan HUANG Jun-hua QIU Hua-ji Division of Swine Infectious Diseases National Key Laboratory of Veterinary Biotechnology Harbin Veterinary Research Institute ChineseAcademy of Agricultural Sciences Harbin 150001 P.R. C＇hina

Classical swine fever （CSF） and porcine reproduction and respiratory syndrome （PRRS） are both economically important, highly contagious diseases of swine worldwide. To develop an effective vaccine to control these two diseases, we constructed a recombinant adenovirus rAdV-GP52AE2, using a replication-defective human adenovirus serotype 5 as a delivery vector, to co-express the GP5 protein of highly pathogenic porcine reproduction and respiratory syndrome virus （PRRSV） and the E2 protein of classical swine fever virus （CSFV）. Foot-and-mouth disease virus （FMDV） 2A peptide was used as a linker between the GP5 and E2 proteins to allow automatic self-cleavage of the polyprotein. The GP5 and E2 genes were expressed as demonstrated by immunofluorescence assay and Western blotting. Immunization of mice resulted in a CSFV-neutralizing antibody titer of 1：128 and a PRRSV-neutralizing antibody titer of 1：16. The lymphoproliferative responses were detected by Cell Counting Kit-8 assay and the stimulation index of CFSV-specific and PRRSV-specific lymphocytes in the rAdV-GP52AE2 group was significantly higher than that in the negative control group. The results show that rAdV-GP52AE2 can induce both effective humoral and cell-mediated immune responses in mice. The protective efficacy of the recombinant virus against CSF was evaluated in immunized rabbits, which were protected from fever induced by challenge with C-strain. Our study provides supporting evidence for the use of FMDV 2A to develop a bivalent genetically-engineered vaccine.

关键词： porcine reproductive and respiratory syndrome virus classical swine fever virus recombinant adenovirus,immunogenicity

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FeS/壳聚糖基碳气凝胶复合材料的制备及对Cr(Ⅵ)的吸附

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化工进展 2023年第11期42卷 6042-6052页

作者：常娟程爱华西安科技大学地质与环境学院陕西西安710054

以壳聚糖为前体材料,通过溶胶-凝胶、冷冻干燥、碳化等方法制备FeS/壳聚糖基碳气凝胶复合材料(FeS/CA-0.5)。利用SEM、FTIR、XRD及XPS等方法对FeS/CA-0.5的微观形态和结构进行了表征,考察了FeS/CA-0.5对Cr(Ⅵ)的吸附性能,探究了反应机... 详细信息

以壳聚糖为前体材料,通过溶胶-凝胶、冷冻干燥、碳化等方法制备FeS/壳聚糖基碳气凝胶复合材料(FeS/CA-0.5)。利用SEM、FTIR、XRD及XPS等方法对FeS/CA-0.5的微观形态和结构进行了表征,考察了FeS/CA-0.5对Cr(Ⅵ)的吸附性能,探究了反应机制。结果表明:FeS/CA-0.5保留壳聚糖基碳气凝胶的结构且成功分散FeS,比表面积大,具有超顺磁性;在100mL 100mg/L的Cr(Ⅵ)溶液中投加0.05g FeS/CA-0.5,pH为2,吸附360min可达到平衡,FeS/CA-0.5对Cr(Ⅵ)的平衡吸附量可达173.84mg/g;吸附过程符合准二级动力学和Langmuir等温吸附模型,颗粒内扩散模型表明FeS/CA-0.5对Cr(Ⅵ)的吸附是多步骤过程,整个吸附过程是自发吸热的;FeS/CA-0.5除铬机制主要是物理吸附、化学吸附及化学还原作用。FeS/CA-0.5在处理含铬废水方面有潜在应用前景。

关键词：生物质碳气凝胶硫化铁复合材料吸附六价铬

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仿生FeS复合材料的制备及其对Cr(Ⅵ)的吸附性能

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复合材料学报 2023年第2期40卷 884-892页

作者：程爱华常娟西安科技大学地质与环境学院西安710054

纳米FeS比表面积大且还原性强,对Cr(Ⅵ)吸附性能优异,但不稳定、易团聚,为解决这一问题,本文以油菜花粉为生物模板,通过共沉淀-焙烧法制得仿生FeS复合材料(bioFeS)。通过SEM、XRD及XPS等方法对bioFeS复合材料的表面微观形态和结构进行... 详细信息

纳米FeS比表面积大且还原性强,对Cr(Ⅵ)吸附性能优异,但不稳定、易团聚,为解决这一问题,本文以油菜花粉为生物模板,通过共沉淀-焙烧法制得仿生FeS复合材料(bioFeS)。通过SEM、XRD及XPS等方法对bioFeS复合材料的表面微观形态和结构进行了表征。以Cr(Ⅵ)为目标污染物,分别考察了吸附剂用量、反应时间、反应温度、初始Cr(Ⅵ)浓度和pH对bioFeS复合材料吸附Cr(Ⅵ)性能的影响,探究了反应机制。结果表明:油菜花粉生物模板成功分散了FeS,制得的bioFeS复合材料比表面积大,在反应时间为120 min、pH值为1、吸附剂投加量为0.2 g·L^(-1)、反应温度为25℃的条件下,bioFeS复合材料对Cr(Ⅵ)的吸附量可达88.95 mg·g^(-1);该吸附过程符合准二级动力学和Langmuir等温吸附模型;共存离子NO_(3)^(-)和SO_(4)^(2-)会抑制Cr(Ⅵ)的去除。结合吸附动力学、热力学及XPS表面元素分析可知bioFeS复合材料除铬机制主要是吸附及化学还原作用。bioFeS复合材料处理含铬废水具有广阔的应用前景。

关键词： FeS 花粉复合材料吸附 Cr(Ⅵ) 生物模板

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