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高潜水位采煤沉陷区微塑料赋存特征及风险评估
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作者 葛建华 丁雨薇 +4 位作者 李佳 张万 马东坡 任雪 张世文 《中国环境科学》 EI CAS CSCD 北大核心 2024年第4期2327-2335,共9页
为探明高潜水位采煤沉陷区微塑料污染赋存特征及其环境风险,选取安徽省淮南市春申湖、舜耕湿地公园两个典型采煤沉陷区为研究区域,采集了表层水体,底泥及周边农田土壤样品,采用体视显微镜、扫描电镜、红外光谱对微塑料尺寸、形状、颜色... 为探明高潜水位采煤沉陷区微塑料污染赋存特征及其环境风险,选取安徽省淮南市春申湖、舜耕湿地公园两个典型采煤沉陷区为研究区域,采集了表层水体,底泥及周边农田土壤样品,采用体视显微镜、扫描电镜、红外光谱对微塑料尺寸、形状、颜色及丰度等赋存特征进行表征.结果表明:采集的样本中多为纤维微塑料和薄膜微塑料,类型主要以聚乙烯,聚丙烯为主,颜色以黄色和透明为主,粒径大多小于500μm.采煤沉陷区的地表水丰度范围为0.77~7.1pcs/L,沉积物微塑料的丰度范围为540~2800pcs/kg,周边农田土壤微塑料的丰度范围为380~2380pcs/kg.采用污染负荷指数(PLI)模型进行评估,地表水和农田土壤的风险评估都为于Ⅰ级,属于轻微污染,而沉积物中的微塑料风险评估为Ⅱ级,属于中度污染. 展开更多
关键词 微塑料 采煤沉陷区 高潜水位 表层水体 土壤 沉积物 风险评估
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Enhanced activation of peroxymonosulfate by Fe/N co-doped ordered mesoporous carbon with dual active sites for efficient removal of m-cresol 被引量:1
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作者 Donghui Li Wenzhe Wu +6 位作者 xue ren Xixi Zhao Hongbing Song Meng Xiao Quanhong Zhu Hengjun Gai Tingting Huang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期130-144,共15页
The novel Fe-N co-doped ordered mesoporous carbon with high catalytic activity in m-cresol removal was prepared by urea-assisted impregnation and simple pyrolysis method.During the preparation of the Fe-NC catalyst,th... The novel Fe-N co-doped ordered mesoporous carbon with high catalytic activity in m-cresol removal was prepared by urea-assisted impregnation and simple pyrolysis method.During the preparation of the Fe-NC catalyst,the complexation of N elements in urea could anchor Fe,and the formation of C3N4during urea pyrolysis could also prevent migration and aggregation of Fe species,which jointly improve the dispersion and stability of Fe.The FeN4sites and highly dispersed Fe nanoparticles synergistically trigger the dual-site peroxymonosulfate (PMS) activation for highly efficient m-cresol degradation,while the ordered mesoporous structure of the catalyst could improve the mass transfer rate of the catalytic process,which together promote catalytic degradation of m-cresol by PMS activation.Reactive oxygen species (ROS) analytic experiments demonstrate that the system degrades m-cresol by free radical pathway mainly based on SO_(4)^(-)·and·OH,and partially based on·OH as the active components,and a possible PMS activation mechanism by 5Fe-50 for m-cresol degradation was proposed.This study can provide theoretical guidance for the preparation of efficient and stable catalysts for the degradation of organic pollutants by activated PMS. 展开更多
关键词 Degradation PEROXYMONOSULFATE Fe(II)/Fe(III)/FeN4 Ordered mesopores carbon Catalyst Radical
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劲性结构钢骨与钢筋连接节点施工技术
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作者 薛韧 张炳宏 《山西建筑》 2024年第8期100-104,共5页
劲性结构在现代建筑结构形式中应用极为广泛,在现场施工中,钢骨构件与钢筋连接节点是现场施工的重点环节,也是建筑结构整体质量保证的关键所在。通过对以往施工项目进行经验总结,将劲性结构钢骨柱与钢筋连接节点进行系统分析与研究,以... 劲性结构在现代建筑结构形式中应用极为广泛,在现场施工中,钢骨构件与钢筋连接节点是现场施工的重点环节,也是建筑结构整体质量保证的关键所在。通过对以往施工项目进行经验总结,将劲性结构钢骨柱与钢筋连接节点进行系统分析与研究,以施工现场常见问题为切入,从设计阶段、加工制造阶段以及现场施工阶段分别进行原因剖析,并梳理汇总了此类连接节点的一般构造做法及优缺点对比等,以指导钢结构施工从业人员在此类型项目中优选合理节点形式解决钢筋连接问题,在保证施工质量前提下,实现降低施工难度,提高施工效率,保障施工安全,节约施工成本的目的。 展开更多
关键词 劲性结构 钢骨柱 连接节点 深化设计 连接件
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谈三维坐标法在钢结构异形项目中的应用
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作者 李亚博 薛韧 +2 位作者 杨宝 杨朝东 郑宇 《山西建筑》 2024年第21期163-167,共5页
三维坐标法在异形钢结构项目中的应用,极大地提高了深化设计、制造和安装的精确度与效率。文中主要探讨三维坐标法在钢结构异形项目中的应用,包括其基本原理、应用优势以及实际案例分析。通过三维坐标法在工程中的应用研究,进一步阐明... 三维坐标法在异形钢结构项目中的应用,极大地提高了深化设计、制造和安装的精确度与效率。文中主要探讨三维坐标法在钢结构异形项目中的应用,包括其基本原理、应用优势以及实际案例分析。通过三维坐标法在工程中的应用研究,进一步阐明其在现代钢结构工程中的重要性和应用前景,为相关领域的工程师和研究人员提供实用的参考与支持。 展开更多
关键词 三维坐标法 异形钢结构 深化设计 制造和安装
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应用CT测量天鼎穴针刺安全深度及角度的研究 被引量:6
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作者 谢伟 张树源 +6 位作者 张宝 陈曦 石磊 薛任 王涛 麻增林 方继良 《中国中西医结合影像学杂志》 2020年第1期8-11,共4页
目的:应用CT测量不同体型患者针刺天鼎穴的针刺安全深度及角度,并探讨针刺安全深度与颈围、罗氏指数的相关性。方法:搜集不同年龄患者135例,按罗氏指数分为瘦长型(A组)、中间型(B组)和矮胖型(C组)3组,每组45例。每组随机选择15例针刺穴... 目的:应用CT测量不同体型患者针刺天鼎穴的针刺安全深度及角度,并探讨针刺安全深度与颈围、罗氏指数的相关性。方法:搜集不同年龄患者135例,按罗氏指数分为瘦长型(A组)、中间型(B组)和矮胖型(C组)3组,每组45例。每组随机选择15例针刺穴位后行CT扫描,以确定针刺路径,其余标记皮肤针刺点后扫描。以C6横突前结节为骨性标志,应用横轴位图像测量针刺点至C6横突前结节的针刺安全深度。以两侧胸锁乳突肌外缘连线为基准线,测量针刺角度。比较3组针刺深度和角度的差异,评估3组安全深度与颈围、罗氏指数的相关性。结果:A组针刺深度:右侧(26.83±0.74)mm,左侧(26.21±1.64)mm;角度:右侧(14.00±1.87)°,左侧(14.25±1.30)°。B组针刺深度:右侧(30.38±1.80)mm,左侧(30.49±2.07)mm;角度:右侧(13.50±1.12)°,左侧(13.50±1.50)°。C组针刺深度:右侧(35.15±9.63)mm,左侧(34.98±9.87)mm;角度:双侧均(13.63±1.87)°。3组针刺深度两两比较差异有统计学意义(均P<0.05),3组针刺角度两两比较差异无统计学意义(均P> 0.05)。A组与C组的针刺深度与颈围呈正相关(P<0.05),3组针刺深度与罗氏指数均呈正相关(均P<0.05)。结论:临床可参考3组针刺安全深度,根据安全深度与颈围、罗氏指数的相关性回归方程,适当改变不同体型患者针刺深度,对达到针刺目的并规避针刺风险有一定帮助。 展开更多
关键词 体层摄影术 X线计算机 针刺 天鼎 安全深度 角度
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改性聚氨酯快速注浆堵水材料的研制及性能 被引量:17
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作者 杨柱 薛忍 +1 位作者 王军 兰支利 《煤田地质与勘探》 CAS CSCD 北大核心 2020年第2期134-140,共7页
在矿山复杂水文地质条件下如何进行快速封堵及动水注浆是注浆领域的技术难题,开发新的化学注浆材料是一个有效的解决途径。通过分析聚氨酯合成反应温度、加料方式、各类助剂、添加剂对比试验,对聚氨酯注浆材料的生产配方进行优化,并确... 在矿山复杂水文地质条件下如何进行快速封堵及动水注浆是注浆领域的技术难题,开发新的化学注浆材料是一个有效的解决途径。通过分析聚氨酯合成反应温度、加料方式、各类助剂、添加剂对比试验,对聚氨酯注浆材料的生产配方进行优化,并确定材料最佳配方。结果表明,以磷酸作为缓凝剂,乙酸乙酯为溶剂,PM-33为催化剂,采用4%纳米二氧化硅改性制得的注浆材料性能较好、遇水膨胀率高、反应过程及产物环保无毒。该研究可为复杂水文地质条件下的注浆工程提供一种新型的单组分水下速凝膨胀聚氨酯注浆材料。 展开更多
关键词 注浆材料 速凝膨胀 聚氨酯 最优配方
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海藻复合肥对夏玉米产量及养分吸收利用的影响 被引量:12
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作者 刘金萍 刘艳丽 +4 位作者 邵雨晴 李银辉 王修康 薛韧 李成亮 《河南农业大学学报》 CAS CSCD 2021年第3期429-434,共6页
为明确新型海藻复合肥在夏玉米上的应用效果,以不施用氮磷钾肥、常规施肥处理为对照,通过大田试验研究了等养分量、减量10%、20%和30%的海藻复合肥对夏玉米产量、生长发育、养分吸收与利用的影响。结果表明,施用等养分量海藻复合肥可促... 为明确新型海藻复合肥在夏玉米上的应用效果,以不施用氮磷钾肥、常规施肥处理为对照,通过大田试验研究了等养分量、减量10%、20%和30%的海藻复合肥对夏玉米产量、生长发育、养分吸收与利用的影响。结果表明,施用等养分量海藻复合肥可促进夏玉米生长发育,显著提高夏玉米产量15.27%,氮磷钾养分积累量显著高于常规施肥,氮、磷、钾肥利用率较常规施肥分别提高29.17%、57.89%、84.21%。海藻复合肥减少10%仍可确保夏玉米稳产,土壤铵态氮、有效磷含量分别显著增加21.06%、15.52%。等养分量海藻复合肥具有较好增产效果、肥料利用率较高,减量10%仍能够维持夏玉米产量及土壤肥力,具有减施增效效果,可在夏玉米生产中推广应用。 展开更多
关键词 海藻复合肥 减施增效 夏玉米 养分累积量 肥料利用率
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Population genomics reveals that natural variation in PRDM16 contributes to cold tolerance in domestic cattle 被引量:4
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作者 Chun-Long Yan Jun Lin +13 位作者 Yuan-Yuan Huang Qing-Shan Gao Zheng-Yu Piao Shou-Li Yuan Li Chen xue ren Rong-Cai Ye Meng Dong Han-Lin Zhang Hui-Qiao Zhou Xiao-Xiao Jiang Wan-Zhu Jin Xu-Ming Zhou Chang-Guo Yan 《Zoological Research》 SCIE CAS CSCD 2022年第2期275-284,共10页
Environmental temperature serves as a major driver of adaptive changes in wild organisms.To discover the mechanisms underpinning cold tolerance in domestic animals,we sequenced the genomes of 28 cattle from warm and c... Environmental temperature serves as a major driver of adaptive changes in wild organisms.To discover the mechanisms underpinning cold tolerance in domestic animals,we sequenced the genomes of 28 cattle from warm and cold areas across China.By characterizing the population structure and demographic history,we identified two genetic clusters,i.e.,northern and southern groups,as well as a common historic population peak at 30 kilo years ago.Genomic scan of cold-tolerant breeds determined potential candidate genes in the thermogenesis-related pathways that were under selection.Specifically,functional analysis identified a substitution of PRDM16(p.P779 L)in northern cattle,which maintains brown adipocyte formation by boosting thermogenesis-related gene expression,indicating a vital role of this gene in cold tolerance.These findings provide a basis for genetic variation in domestic cattle shaped by environmental temperature and highlight the role of reverse mutation in livestock species. 展开更多
关键词 Population genomics CATTLE Cold tolerance PRDM16 Brown adipose tissue
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Periodically varied initial offset boosting behaviors in a memristive system with cosine memductance 被引量:4
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作者 Mo CHEN xue ren +2 位作者 Hua-gan WU Quan XU Bo-cheng BAO 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2019年第12期1706-1716,共11页
A four-dimensional memristive system is constructed using a novel ideal memristor with cosine memductance. Due to the special memductance nonlinearity, this memristive system has a line equilibrium set(0, 0, 0, δ) lo... A four-dimensional memristive system is constructed using a novel ideal memristor with cosine memductance. Due to the special memductance nonlinearity, this memristive system has a line equilibrium set(0, 0, 0, δ) located along the coordinate of the inner state variable of the memristor, whose stability is periodically varied with a change of δ. Nonlinear and one-dimensional initial offset boosting behaviors, which are triggered by not only the initial condition of the memristor but also other two initial conditions, are numerically uncovered. Specifically, a wide variety of coexisting attractors with different positions and topological structures are revealed along the boosting route. Finally, circuit simulations are performed by Power SIMulation(PSIM) to confirm the unique dynamical features. 展开更多
关键词 Initial offset boosting Memristive system Memductance Line equilibrium set
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Equisetin is an anti-obesity candidate through targeting 11β-HSD1 被引量:1
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作者 Zhenlu Xu Dongyun Liu +10 位作者 Dong Liu xue ren Haibo Liu Guihong Qi Yue Zhou Chongming Wu Kui Zhu Zhongmei Zou Jing Yuan Wenhan Lin Peng Guo 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2022年第5期2358-2373,共16页
Obesity is increasingly prevalent globally, searching for therapeutic agents acting on adipose tissue is of great importance. Equisetin(EQST), a meroterpenoid isolated from a marine sponge-derived fungus, has been rep... Obesity is increasingly prevalent globally, searching for therapeutic agents acting on adipose tissue is of great importance. Equisetin(EQST), a meroterpenoid isolated from a marine sponge-derived fungus, has been reported to display antibacterial and antiviral activities. Here, we revealed that EQST displayed anti-obesity effects acting on adipose tissue through inhibiting adipogenesis in vitro and attenuating HFD-induced obesity in mice, doing so without affecting food intake, blood pressure or heart rate.We demonstrated that EQST inhibited the enzyme activity of 11β-hydroxysteroid dehydrogenase type 1(11β-HSD1), a therapeutic target of obesity in adipose tissue. Anti-obesity properties of EQST were all offset by applying excessive 11β-HSD1’s substrates and 11β-HSD1 inhibition through knockdown in vitro or 11β-HSD1 knockout in vivo. In the 11β-HSD1 bypass model constructed by adding excess11β-HSD1 products, EQST’s anti-obesity effects disappeared. Furthermore, EQST directly bond to11β-HSD1 protein and presented remarkable better intensity on 11β-HSD1 inhibition and better efficacy on anti-obesity than known 11β-HSD1 inhibitor. Therefore, EQST can be developed into anti-obesity candidate compound, and this study may provide more clues for developing higher effective 11β-HSD1 inhibitors. 展开更多
关键词 EQST OBESITY ADIPOCYTE Lipid accumulation Preadipocyte differentiation Adipose tissue 11β-HSD1 11β-HSD1 inhibitor
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Comparative and population genomics of buckwheat species reveal key determinants of flavor and fertility
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作者 Kaixuan Zhang Yuqi He +23 位作者 Xiang Lu Yaliang Shi Hui Zhao Xiaobo Li Jinlong Li Yang Liu Yinan Ouyang Yu Tang xue ren xuemei Zhang Weifei Yang Zhaoxia Sun Chunhua Zhang Muriel Quinet Zlata Luthar Mateja Germ Ivan Kreft Dagmar Janovska Vladimir Meglic Barbara Pipan Milen I.Georgiev Bruno Studer Mark A.Chapman Meiliang Zhou 《Molecular Plant》 SCIE CSCD 2023年第9期1427-1444,共18页
Common buckwheat(Fagopyrum esculentum)is an ancient crop with a world-wide distribution.Due to its excellent nutritional quality and high economic and ecological value,common buckwheat is becoming increasingly importa... Common buckwheat(Fagopyrum esculentum)is an ancient crop with a world-wide distribution.Due to its excellent nutritional quality and high economic and ecological value,common buckwheat is becoming increasingly important throughout the world.The availability of a high-quality reference genome sequence and population genomic data will accelerate the breeding of common buckwheat,but the high heterozygosity due to the outcrossing nature has greatly hindered the genome assembly.Here we report the assembly of a chromosome-scale high-quality reference genome of F.esculentum var.homotropicum,a homozygous self-pollinating variant of common buckwheat.Comparative genomics revealed that two cultivated buckwheat species,common buckwheat(F.esculentum)and Tartary buckwheat(F.tataricum),underwent metabolomic divergence and ecotype differentiation.The expansion of several gene families in common buckwheat,including FhFAR genes,is associated with its wider distribution than Tartary buckwheat.Copy number variation of genes involved in the metabolism of flavonoids is associated with the difference of rutin content between common and Tartary buckwheat.Furthermore,we present a comprehensive atlas of genomic variation based on whole-genome resequencing of 572 accessions of common buckwheat.Population and evolutionary genomics reveal genetic variation associated with environmental adaptability and floral development between Chinese and non-Chinese cultivated groups.Genome-wide association analyses of multi-year agronomic traits with the content of flavonoids revealed that Fh05G014970 is a potential major regulator of flowering period,a key agronomic trait controlling the yield of outcrossing crops,and that Fh06G015130 is a crucial gene underlying flavor-associated flavonoids.Intriguingly,we found that the gene translocation and sequence variation of FhS-ELF3 contribute to the homomorphic self-compatibility of common buckwheat.Collectively,our results elucidate the genetic basis of speciation,ecological adaptation,fertility,and unique flavor of common buckwheat,and provide new resources for future genomics-assisted breeding of this economically important crop. 展开更多
关键词 BUCKWHEAT genomics natural variation adaptation FLAVONOIDS FAGOPYRUM
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Outcomes of allograft from donor kidney microthrombi and secondary recipient thrombotic microangiopathy: should we consider loosening the belt?
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作者 Yamei CHENG Luying GUO +8 位作者 xue ren Zhenzhen YANG Junhao LV Huiping WANG Wenhan PENG Hongfeng HUANG Jianyong WU Jianghua CHEN rending WANG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2023年第6期524-529,共6页
There is currently a huge worldwide demand for donor kidneys for organ transplantation.Consequently,numerous marginal donor kidneys,such as kidneys with microthrombi,are used to save patients'lives.While some stud... There is currently a huge worldwide demand for donor kidneys for organ transplantation.Consequently,numerous marginal donor kidneys,such as kidneys with microthrombi,are used to save patients'lives.While some studies have shown an association between the presence of microthrombi in donor kidneys and an increased risk for delayed graft function(DGF)(McCall et al.,2003;Gao et al.,2019),other studies have demonstrated that microthrombi negatively impact the rate of DGF(Batra et al.,2016;Hansen et al.,2018),but not graft survival rate(McCall et al.,2003;Batra et al.,2016;Gao et al.,2019).In contrast,Hansen et al.(2018)concluded that fibrin thrombi were not only associated with reduced graft function six months posttransplantation but also with increased graft loss within the first year of transplantation.On the other hand,Batra et al.(2016)found no significant differences in the DGF rate or one-year graft function between recipients in diffuse and focal microthrombi groups.To date,however,the overall influence of donor kidney microthrombi and the degree of influence on prognosis remain controversial,necessitating further research. 展开更多
关键词 KIDNEY throm DONOR
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