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Fabrication of double crosslinked chitosan/gelatin membranes with Na⁺ and pH dual-responsive controlled permeability

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CARBOHYDRATE POLYMERS 2020年第0期236卷 115963-000页

作者： Liu, Jin Wang, Shunyi Xu, Ke Fan, Zaibi Wang, Panpan Xu, Zijun ren, Xueqin Hu, shuwen Gao, Zideng China Agr Univ Coll Resources & Environm Sci Beijing 100193 Peoples R China China Agr Univ Beijing Key Lab Farmland Soil Pollut Prevent & Re Beijing 100193 Peoples R China Minist Land & Resources China Key Lab Agr Land Qual Beijing 100193 Peoples R China

A double crosslinked membrane based on chitosan/gelatin with controlled release properties was synthesized in aqueous system using potassium pyroantimonate and genipin as the ionic crosslinker and covalent crosslinker, respectively. The membranes were characterized using FT-IR, UV-vis spectra, and SEM. In addition, the thermal stability, contact angle, mechanical and controlled release properties were measured. Double-crosslinking significantly improved the hydrophobicity, thermal stability, and tensile strength of the membrane. The permeabilities of various plant nutrients, including urea and plant growth regulators (PGRs), were evaluated. Under the optimized conditions, the lowest flux (J) of urea was 2.89 mg/(cm(2).h). Urea and PGR release were sustained for up to 3 and 10 days, respectively. The release of agrochemicals in this study followed the Weibull model, demonstrating the Na+-responsive and pH-responsive permeability of the films. This dual-responsive film has potential applications in salinized barrier soil, water treatment, separations, and other membrane applications.

关键词： chitosan/gelatin Double crosslinked Dual-responsive Controlled permeability Membrane

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城市轨道交通线路减振扣件性能试验方法研究

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城市轨道交通研究 2018年第4期21卷 18-20,24页

作者：冯光福张小华谢华支李峰任树文南宁轨道交通集团有限责任公司南宁高级工程师530021 中国船舶重工集团公司第七一一研究所上海201108 中铁工程设计咨询集团有限公司北京100055

轨道交通减振扣件的性能直接影响到运营安全和对周边环境的影响,如何准确试验得到其性能参数成为线路振动噪声评估和优化设计的关键。通过QY-2型减振扣件的静、动态特性试验研究,总结出根据实际使用工况合理选择载荷范围、通过动态扫频... 详细信息

轨道交通减振扣件的性能直接影响到运营安全和对周边环境的影响,如何准确试验得到其性能参数成为线路振动噪声评估和优化设计的关键。通过QY-2型减振扣件的静、动态特性试验研究,总结出根据实际使用工况合理选择载荷范围、通过动态扫频试验法直接获得减振扣件共振频率的试验方法,该方法能有效表征减振扣件的性能。

关键词：城市轨道交通减振降噪扣件试验方法

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The Accumulation of Plant- and Microbial-Derived Carbon and its Contribution to Soil Organic Carbon in Saline-Sodic Farmland

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SSRN 2024年

作者： Zhou, Tairan Fan, Jingbiao Zhang, Luxin Lv, Qilin Wang, Tianhao Meng, Yunshan Hu, Hao Gao, Haixiang Wang, Jie ren, Xueqin Gao, Zideng Hu, shuwen College of Resources and Environment Sciences China Agricultural University No. 2 Yuanmingyuan west road Haidian District Beijing100193 China Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation No. 2 Yuanmingyuan west road Haidian District Beijing100193 China Beijing Dabeinong Technology Group Co. Ltd Zhongguancun dajie 27 Haidian District Beijing100080 China

Saline-sodic soils have experienced severe organic carbon loss worldwide. In recent years, various types of cropping systems have been employed to reclaim saline-sodic wastelands, with the aim of increasing food production and improving soil conditions. However, the complex effects of this rapid and intense land-use change on soil organic carbon (SOC) accumulation and stability remain unclear. In this study, we compared how these effects varied across unperturbed saline-sodic wasteland, paddy fields, upland fields, and upland fields converted from paddy fields (CF) in the Songnen Plain, northeast China. Our assessment of plant- and microbial-derived carbon biomarkers, including lignin phenols, amino sugars, and glomalin-related soil proteins, revealed that the cultivation of saline-sodic wasteland increased total SOC by increasing particulate, mineral-associated, and labile organic carbon. Across cropping systems, the largest increase in SOC (217.77%) was measured under long-term cultivation. Microbial-derived carbon was the primary contributor to SOC in saline-sodic farmland, but the proportion of SOC formed by plant-derived carbon increased under long-term cultivation. Our analysis of lignin phenols and soil enzymes (cellulase and ligninase) suggests that microbial decomposition of plant-derived carbon was enhanced in long-term compared to short-term farmland. Despite greater overall accumulation of plant- and microbial-derived carbon in CF, the stability of microbial-derived carbon in this cropping system was relatively low due to lower ratios of glucosamine to muramic acid. Additionally, random forest modelling indicates that the increases in microbial biomass and improvements in basic soil properties associated with the cultivation of saline-sodic wasteland were the key factors influencing plant- and microbial-derived carbon. These findings demonstrate that the cultivation of saline-sodic wasteland increases carbon sequestration in the soil by increasing both p

关键词： Organic carbon

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Sources and Cycling of Dissolved Organic and Inorganic Carbon on the Northern Qinghai-Tibetan Plateau: Radiocarbon Results from Qinghai Lake

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SSRN 2022年

作者： Wang, Xuchen Zhang, Hongmei Wang, Fuqiang Shan, Sen ren, Peng Luo, Chunle Fu, Wenjing Sun, shuwen Frontiers Science Center for Deep Ocean Multispheres and Earth System Key Laboratory of Marine Chemistry Theory and Technology Ocean University of China Qingdao China Qingdao National Laboratory for Marine Science and Technology Qingdao China North China Sea Environmental Monitoring Center State Oceanic Administration Qingdao China Center for Isotope Geochemistry and Geochronology Qingdao National Laboratory for Marine Science and Technology Qingdao China

We present the concentrations and carbon isotope compositions of dissolved organic and inorganic carbon (DOC and DIC) combined with major lithologic ions in Qinghai Lake and its seven inflowing rivers on the northeastern Qinghai-Tibetan Plateau of China. Our results revealed large differences in concentrations and isotopic compositions between DOC and DIC, as well as concentrations of major ions in the rivers and lake. The chemical weathering of carbonate and silicates played important roles in controlling the fates of major ions in the rivers. In Qinghai Lake, evaporation resulted in the accumulation of Na+, Mg2+, and K+, while biological uptake and precipitation reduced the concentrations of Ca2+ and Si4+ in the lake compared with those in the rivers. Concentrations of DOC and DIC in the lake are much higher than the DOC and DIC concentrations carried by the rivers. The rivers transport millennium-aged DOC (1254 ± 316 years) and DIC (1513 ± 857 years), as influenced largely by the chemical weathering of rocks and preaged soil carbon on the plateau. In Qinghai Lake, the ages of DOC are significantly younger than the ages of riverine DOC, as regulated by phytoplankton-produced modern DOC. In contrast, the DIC ages in Qinghai Lake are all modern, indicating that exchange with atmospheric CO2 is the dominant process controlling the lake DIC. The accumulation and removal of riverine-aged DIC in Qinghai Lake, however, are not well understood, and the unbalanced radiocarbon in lake DIC remains an unsolved mystery that needs to be further studied. © 2022, The Authors. All rights reserved.

关键词： Rivers

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Impacts of Long-Term Rice Cultivation on Phosphorus Transformations in Saline-Sodic Soils of the Songnen Plain, China

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SSRN 2023年

作者： Lv, Qilin Zhang, Yun Zou, Li Fan, Jingbiao Wei, Tongyu Zhou, Tairan Wang, Jie ren, Xueqin Gao, Haixiang Prof, shuwen Hu College of Resources and Environment Sciences China Agricultural University Beijing China Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation Beijing China Department of Applied Chemistry China Agricultural University Beijing China College of Resources and Environment Sciences China Agricultural University No. 2 Yuanmingyuan west road Haidian District Beijing100193 China

The perpetual cultivation of rice within saline-sodic wastelands has been observed to enhance soil nutrient availability and promote microbial growth. Nevertheless, the impacts of such a reclamation process on the fractions of inorganic phosphorus (Pi) in saline and sodic soils remain elusive. A comprehensive investigation was undertaken to examine the transformations of Pi that occur within saline-sodic soils subjected to long-term rice cultivation. This study encompassed an analysis of the chemical properties, Pi fractions, and levels of microbial phospholipid fatty acids (PLFAs) within the widely sampled plow layer (0-20 cm) of soils that had undergone 1, 5, 10, 20, 29, and 51 years of rice cultivation. Upon a continuous decrease in electrical conductivity (EC), the soil organic matter attained its zenith subsequent to 20 years of rice cultivation (34.05 ± 3.95 g kg-1), and subsequently sustained stability (21.58–32.07 g kg-1). An escalating trend was discerned in available phosphorus and microbial biomass phosphorus during the protracted cultivation period within the saline-sodic soil. In the nascent phases of cultivation (0, 1, 5, and 10 years), the Ca-P ratio constituted 64%, 71%, 57%, and 61% of the inorganic phosphorus pool within the soil, respectively. However, at the intermediate (20 and 29 years) and advanced stages (51 years), Al-P and Fe–P emerged as the predominant phosphorus fractions across all samples, accounting for 40%, 57%, and 53% of the inorganic phosphorus pool, respectively. Amendment of the saline-alkali soil bolstered the Fe/Al oxide content and fostered accumulation of the Fe-P pool with the increasing years of rice cultivation. Partial Least Squares Path Modeling (PLS-PM) elucidated that while the salinity and sodicity exhibited an indirect influence on inorganic phosphorus fractions, nutrients (SOM, STN, STP, Po and Fe/Al oxides) played a vital role in the transformation of inorganic phosphorus fractions. Consequently, alterations in nu

关键词： Soils

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长春市城市热岛效应月变化特征及其影响因素

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生态学杂志 2024年第8期43卷 2257-2265页

作者：潘立志杨朝斌任志彬张树文徐新良隗彤刘丽峰山东理工大学建筑工程学院山东淄博255000 中国科学院生态环境研究中心城市与区域生态国家重点实验室北京100085 华东师范大学上海市城市化生态过程与生态恢复重点实验室上海200241 中国科学院东北地理与农业生态研究所长春130102 中国科学院地理科学与资源研究所资源与环境信息系统国家重点实验室北京100101

城市热岛效应已成为阻碍城市可持续发展的重要生态环境问题,然而有关我国寒冷地区城市热岛效应季节变化的研究相对较少,限制了对不同气候区城市热岛效应的全面理解。本文以我国东北地区典型城市吉林省长春为例,综合Landsat 8和高分辨率... 详细信息

城市热岛效应已成为阻碍城市可持续发展的重要生态环境问题,然而有关我国寒冷地区城市热岛效应季节变化的研究相对较少,限制了对不同气候区城市热岛效应的全面理解。本文以我国东北地区典型城市吉林省长春为例,综合Landsat 8和高分辨率遥感影像GF2等数据,提出4个地表热岛效应强度指标,结合光谱解混模型、剖面线分析以及回归模型等方法探究热环境月变化规律以及潜在驱动因子对热岛效应季节变化的影响。结果表明:(1)长春热环境空间格局具有显著的月变化和季节变化规律,8月温度最高(39.44℃),12月最低(-18.60℃);冬夏两季存在明显城市热岛效应而春秋两季不明显。(2)不同指标表征的城市热岛效应强度存在明显差异;基于土地利用类型差异表示的热岛强度在7月可高达10.56℃,而部分月份(2月、3月和11月)甚至呈现出农村温度高于城市的“逆城市热岛效应”。(3)植被和不透水地表面积是影响城市热环境时空变化的重要驱动因子,且影响机制存在明显的季节性变化规律,两者之间在夏季拥有最显著相关关系,而冬季几乎不产生影响。(4)城市功能区热环境特征同样存在显著季节性差异,工业区等人造建筑密集的区域地表温度较高,但人类活动如秸秆焚烧等使农田在部分月份拥有最高的地表温度。本研究阐明了城市热环境月变化和季节变化的驱动机制,对寒冷地区热环境生态的调控具有重要意义。

关键词：城市热岛效应地表温度逐月变化影响因素寒冷区域

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稻米适度加工及其品质综合评价研究进展

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食品科技 2023年第6期48卷 125-130页

作者：张珊洪滨沙迪新袁迪冯俊然任传英卢淑雯黑龙江省农业科学院食品加工研究所黑龙江哈尔滨150086 黑龙江省食品加工重点实验室黑龙江哈尔滨150086

稻米加工是粮食生产过程中的一个重要环节,而消费者对大米感官品质的过度追求所引发的稻米过度加工,使得稻米所含营养物质大量损失。降低稻米加工精度,虽然营养物质得到保留,但感官品质下降。文章分别从稻米适度加工技术与产品,适度加... 详细信息

稻米加工是粮食生产过程中的一个重要环节,而消费者对大米感官品质的过度追求所引发的稻米过度加工,使得稻米所含营养物质大量损失。降低稻米加工精度,虽然营养物质得到保留,但感官品质下降。文章分别从稻米适度加工技术与产品,适度加工过程引发的营养品质、食用品质、贮藏品质和安全品质变化进行剖析,并对稻米的综合品质评价手段进行概述,最后对适度加工稻米的综合品质评价进行展望,旨在为寻找一个适度加工稻米营养品质与食用品质兼具的平衡点提供一定的参考依据。

关键词：稻米适度加工品质评价

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Deconvolution reveals cell-type-specific transcriptomic changes in the aging mouse brain

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SCIENTIFIC REPORTS 2023年第1期13卷 1-12页

作者： ren, Yingxue Wang, Xue Zhang, shuwen Hu, Hongru Quicksall, Zachary Lee, Sangderk Morganti, Josh M. Johnson, Lance A. Asmann, Yan W. Zhao, Na Mayo Clin Dept Quantitat Hlth Sci 4500 San Pablo Rd South Jacksonville FL 32224 USA Mayo Clin Dept Quantitat Hlth Sci Rochester MN 55905 USA Univ Calif Davis Genome Ctr Davis CA 95616 USA Univ Kentucky Sanders Brown Ctr Aging Lexington KY 40536 USA Univ Kentucky Dept Neurosci Lexington KY 40536 USA Univ Kentucky Dept Physiol Lexington KY 40536 USA Mayo Clin Dept Neurosci 4500 San Pablo Rd South Jacksonville FL 32224 USA

Mounting evidence highlights the crucial role of aging in the pathogenesis of Alzheimer's disease (AD). We have previously explored human apoE-targeted replacement mice across different ages and identified distinct molecular pathways driven by aging. However, the specific contribution of different brain cell types to the gene modules underlying these pathways remained elusive. To bridge this knowledge gap, we employed a computational deconvolution approach to examine cell-type-specific gene expression profiles in major brain cell types, including astrocytes (AS), microglia (MG), oligodendroglia (OG), neurons (NEU), and vascular cells (VC). Our findings revealed that immune module genes were predominantly expressed in MG, OG, and VC. The lipid metabolism module genes were primarily expressed in AS, MG, and OG. The mitochondria module genes showed prominent expression in VC, and the synapse module genes were primarily expressed in NEU and VC. Furthermore, we identified intra- and inter-cell-type interactions among these module genes and validated their aging-associated expression changes using published single cell studies. Our study dissected bulk brain transcriptomics data at the cellular level, providing a closer examination of the cell-type contributions to the molecular pathways driven by aging.

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腐殖酸钾对杨梅土壤改良和生长结实的影响

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浙江农业学报 2024年第8期36卷 1878-1886页

作者：孙鹂张淑文俞浙萍郑锡良梁森苗任海英戚行江浙江省农业科学院园艺研究所浙江杭州310021 湘湖实验室浙江杭州311231

针对杨梅种植区土壤环境恶化导致杨梅树体衰弱、果实品质下降的问题,开展腐殖酸钾调理杨梅根系土壤的研究,施用不同剂量的腐殖酸钾,测定土壤理化性质,微生物生物量碳、氮,土壤酶活性,以及杨梅茎、叶的营养元素含量,果实品质与产量的变... 详细信息

针对杨梅种植区土壤环境恶化导致杨梅树体衰弱、果实品质下降的问题,开展腐殖酸钾调理杨梅根系土壤的研究,施用不同剂量的腐殖酸钾,测定土壤理化性质,微生物生物量碳、氮,土壤酶活性,以及杨梅茎、叶的营养元素含量,果实品质与产量的变化。结果表明,施用腐殖酸钾可显著(P<0.05)提高土壤pH值、阳离子交换量、电导率和最大持水量,显著增加土壤速效氮、速效钾含量和土壤交换性钙含量,显著提高土壤脲酶、蔗糖酶、过氧化氢酶活性,显著增加杨梅茎、叶的钾、钙含量,显著提高杨梅果实的总糖和可溶性糖含量,显著促进花色素苷的积累,显著提升杨梅的商品果率和优质果率。综上,腐殖酸钾可作为适宜的土壤调理剂,改善杨梅根系的土壤健康状况,提高杨梅果实品质。

关键词：杨梅腐殖酸钾土壤改良树体营养果实品质

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不同光质补光对杨梅花芽发育的影响

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果树学报 2023年第3期40卷 527-535页

作者：孙鹂张淑文郑锡良俞浙萍任海英梁森苗戚行江浙江省农业科学院园艺研究所杭州310021 湘湖实验室杭州311231

【目的】探究不同光质补光处理对杨梅花芽分化和开花进程的影响。【方法】在相同设施条件下,采用色温3329 K的LED白光灯和色温1531 K的LED红光灯对杨梅树进行补光处理,测定树体周围光照度、叶片叶绿素含量、花芽数量和大小,通过形态和... 详细信息

【目的】探究不同光质补光处理对杨梅花芽分化和开花进程的影响。【方法】在相同设施条件下,采用色温3329 K的LED白光灯和色温1531 K的LED红光灯对杨梅树进行补光处理,测定树体周围光照度、叶片叶绿素含量、花芽数量和大小,通过形态和解剖观察花芽的萌发及发育状态,以明确不同光质补光处理对杨梅花芽生长的影响。【结果】2种光质补光处理均显著改善树体周围光环境,其中白光处理显著提高树体周围光照度。红光处理下杨梅分化形成的花芽数目最多,同期花芽最大、发育最快,利于提前花期;白光处理也在一定程度上促进花芽生长发育,但花芽数目、花芽纵横径以及花芽发育状态都弱于红光处理;对照组的花芽数量最少,萌发最晚。表明2种不同光质的补光处理均有利于花芽发育,其中较高比例红光的促进效果最为明显。【结论】对设施栽培杨梅树进行补光处理,可显著增加花芽数目,提高花芽纵横径,促进提早开花。其中红光处理促进作用优于白光处理。该研究结果对杨梅设施栽培具有指导作用。

关键词：杨梅不同光质补光花芽发育

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