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二氧化锆掺杂聚多巴胺纳米复合涂层的制备及其对环境水样中多环芳烃的高效固相微萃取

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分析化学 2025年第1期53卷 143-151页

作者：沈小燕王会菊韩柳马贞青海民族大学化学与材料科学学院青海民族大学青藏高原资源化学与生态环境保护国家民委重点实验室

二氧化锆（ZrO2）具有热稳定性高、化学稳定性好和吸附性能优异等特性，可作为固相微萃取（SPME）的纤维涂层。聚多巴胺（PDA）具有抗氧化性强、稳定性高、吸附能力强以及环境友好等优点，也常被用作SPME的纤维涂层。本研究采用循环伏... 详细信息

二氧化锆（ZrO2）具有热稳定性高、化学稳定性好和吸附性能优异等特性，可作为固相微萃取（SPME）的纤维涂层。聚多巴胺（PDA）具有抗氧化性强、稳定性高、吸附能力强以及环境友好等优点，也常被用作SPME的纤维涂层。本研究采用循环伏安法在不锈钢丝（SS）表面快速构筑二氧化锆掺杂聚多巴胺（ZrO2@PDA）纳米复合膜作为SPME的纤维涂层。将制备的SS@ZrO2@PDA纤维与高效液相色谱（HPLC）联用，考察了其对4类典型芳香化合物的富集萃取能力。结果显示，SS@ZrO2@PDA纤维对多环芳烃（PAHs）和钛酸酯（PAEs）类化合物的萃取能力强，对紫外线吸收剂（UvFs）的萃取能力弱，而对氯酚（CPs）类化合物几乎不萃取。在优化的实验条件下，采用SS@ZrO2@PDA纤维结合HPLC法对5种PAHs进行富集和测定，各目标物在各自的浓度范围内线性关系良好，线性相关系数（R）>0.9986，检出限（LODs, S/N=3）为0.018～0.082μg/L。将本方法用于环境水样中目标PAHs的富集分析，加标回收率为86.7%～102.4%，相对标准偏差（RSDs）<8.2%。SS@ZrO2@PDA纤维制备简单、稳定性高、重现性好、使用寿命长，有良好的应用潜能。

关键词：二氧化锆聚多巴胺循环伏安纳米复合涂层固相微萃取多环芳烃

来源：博看期刊

基于共价有机骨架的水凝胶固相萃取在农药检测中的应用

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分析测试学报 2025年第1期44卷 145-154页

作者：孙蕾刘凌志刘玉碟沈晓芳新疆维吾尔自治区产品质量监督检验研究院新疆乌鲁木齐830011 江南大学食品学院江苏无锡214122

食品中农药残留超标对生物多样性以及人类健康造成潜在威胁。固相萃取技术广泛应用于农药的萃取,该方法的核心是吸附材料的选择。共价有机骨架(COFs)材料因其独特的优点在样品预处理中得到广泛的关注,而COFs的结构决定了材料的吸附性能... 详细信息

食品中农药残留超标对生物多样性以及人类健康造成潜在威胁。固相萃取技术广泛应用于农药的萃取,该方法的核心是吸附材料的选择。共价有机骨架(COFs)材料因其独特的优点在样品预处理中得到广泛的关注,而COFs的结构决定了材料的吸附性能,这对提高农药的萃取效果有重要作用。该研究制备了6种不同结构与性质的COFs(同一母体接枝不同官能团、具有不同带电性质、具有不同共轭结构),在不改变COFs结构的情况下,将其制备为COFs-海藻酸钠水凝胶(CACPs),建立了CACPs-分散固相萃取(CACPs-dSPE)方法,比较不同CACPs对氨基甲酸酯类、三唑类以及三嗪类农药的萃取效果。利用扫描电子显微镜、傅里叶变换红外光谱、X射线晶体衍射等方法对系列COFs以及系列CACPs的形貌、结构与性质进行表征。CACPs-dSPE结合高效液相色谱(HPLC)或紫外-可见分光光度法(UV-Vis)探究萃取效果,并结合理论计算模拟COFs与待测物的结合情况,探讨了不同CACPs对氨基甲酸酯类、三唑类以及三嗪类农药的吸附机理。结果表明:CACPs对不同类型农药的吸附性能是由其多孔结构性质(比表面积、孔径大小)和所负载COFs的固有结构协调决定,大的共轭结构、接枝羟基基团的COFs所制备的CACPs最有利吸附三类农药,其中Dt-TAPB-CACPs的萃取效果最佳。这为萃取农药过程中吸附材料的选择和设计提供了理论指导。

关键词：农药残留共价有机骨架 COFs-海藻酸钠水凝胶分散固相萃取(dSPE) 吸附机理

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水平井钻井施工过程中风险分析及对策研究

西部探矿工程 2025年第2期37卷 189-191+195页

作者：沈晓鹏大庆钻探工程公司定向井技术服务项目经理部

钻井工程作为石油工程领域的重要组成部分之一，具有现场规模大、施工周期长、资金投入高等特点。受地质条件、作业环境和施工方法与参数等因素影响，钻井施工也是石油工程领域中具有较高风险的环节之一。为进一步提高水平井钻井工程项... 详细信息

钻井工程作为石油工程领域的重要组成部分之一，具有现场规模大、施工周期长、资金投入高等特点。受地质条件、作业环境和施工方法与参数等因素影响，钻井施工也是石油工程领域中具有较高风险的环节之一。为进一步提高水平井钻井工程项目的风险管理水平，对国内外水平井钻井风险管理理论与技术进行了调研。按钻前、钻进和钻后三个部分对钻井工程施工风险进行了总结，并对影响钻井工程安全的主要因素进行了分析。提出了四个方面的钻井施工风险对策，以期为相关从业者在降低水平井钻井施工安全风险，提高水平井钻井施工安全管理水平方面提供技术参考。

关键词：钻井施工安全风险风险评估风险管理施工安全

钢筋混凝土拱桥0^(#)节段现浇支架设计与分析

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价值工程 2025年第2期44卷 113-115页

作者：申晓平中铁十七局集团城市建设有限公司贵阳550000

本文依托贵州省金沙经仁怀至桐梓高速公路项目,采用有限元分析软件对娅石庆钢筋混凝土拱桥两岸0~#节段进行分析验算。拱桥0^(#)节段重量较重,且拱段为倾斜结构,通过底模板传递给支架的荷载不仅有竖直荷载,而且还有较大的水平荷载。支架... 详细信息

本文依托贵州省金沙经仁怀至桐梓高速公路项目,采用有限元分析软件对娅石庆钢筋混凝土拱桥两岸0~#节段进行分析验算。拱桥0^(#)节段重量较重,且拱段为倾斜结构,通过底模板传递给支架的荷载不仅有竖直荷载,而且还有较大的水平荷载。支架设计中通过沿纵桥向设置3排竖向钢管支撑来承载竖向荷载,在拱座内埋设型钢及钢板与纵向水平横杆焊接来抵抗支架承受的水平荷载。验算中采用支架自重、节段钢筋混凝土湿重、施工荷载等荷载组合对现浇支架的刚度、强度、稳定性、基础承载进行分析,支架的刚度、强度、稳定性及临时基础的弯矩、剪力均满足设计规范要求,具有类似工程施工经验借鉴作用。

关键词：有限元分析钢筋混凝土拱桥 0^(#)节段现浇支架

维普期刊数据库博看期刊

Effect of Nitrogenous Fertilizer Treatment on Mineral Metabolism in Grazing Yaks

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Agricultural Sciences in China 2009年第3期8卷 361-368页

作者： shen xiao-yun Department of Biology Chongqing University of Science and Technology Chongqing 401331 P.R.China Key Laboratory of Animal Ecology and Conservation Biology Institute of Zoology Chinese Academy of Sciences Beijing 100101 P.R. China

To assess the impact of N fertilization on contents of mineral elements in herbage and the effect of increased forage S on the copper metabolism of grazing yaks, study was conducted during the summer grazing season （2005, 2006, and 2007）. Pasture replicates （20 ha; n=3 per treatment） received the same fertilizer treatment in each growing season, consisting of i） 90 kg N ha^-1 from quickly available nitrogen, ii） 90 kg N ha^-1 from ammonium nitrate, iii） 90 kg N ha^-1 from ammonium sulfate, and iv） control （no fertilizer）. Forage sampling was collected at 60 days intervals following fertilization （10 samples per pasture） for Cu, Mo, Mn, Se, Fe, Zn, Ca, and P. To determine the effect of fertilizer treatment on mineral metabolism in grazing yaks, liver and blood samples were collected at the start and end of the study period in 2005, 2006, and 2007. Ammonium sulfate fertilization increased （P 〈 0.01） forage S concentration. Plant tissue N concentrations were increased by N fertilization, regardless of source in 2005, 2006, and 2007. Yaks grazing S fertilization pastures had lower （P〈0.05） liver and blood Cu concentrations at the end of the study period in 2005, 2006, and 2007, compared with urea, ammonium nitrate, and control. Nominal increases in forage in vitro organic matter digestibility were realized by fertilization, regardless of N source in each year.

关键词： yaks nitrogen fertilizer treatment alpine meadow forage mineral element metabolism

Studies on Wool-Eating Ailment in Guizhou Semi-Fine Wool Sheep

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Agricultural Sciences in China 2011年第10期10卷 1618-1623页

作者： shen xiao-yun College of Chemistry ＆ Chemical Engineering Chongqing University of Science and Technology Chongqing 401331 P.R. China Key Laboratory of Animal Ecology and Conservation Biology Institute of Zoology Chinese Academy of Sciences Beijing 100101 P.R China Pratacultural Ecology Institute Bijie University Bijie 551700 P.R.China

The clinical symptoms of a disorder which is known locally as ＂wool-eating ailment＂ in Guizhou semi-fine wool sheep in the Weining County of Guizhou Province, China, are poor weight gain, lost appetite, pica, emaciation, and wool-eating. The mineral composition of forage, and samples of blood, liver and wool from Guizhou semi-fine wool sheep in affected ranches were compared with those from the unaffected areas. The mean concentration of iron in forage from affected pasture was significantly higher than that from the unaffected pasture. The mean concentration of sulfur in forage from the affected and unaffected pasture was similar and within normal ranges. The mean concentration of sulfur in blood, liver and wool from the affected Guizhou semi-fine wool sheep was significantly lower than that from the unaffected sheep while the content of iron in blood, liver and wool from the affected sheep was significantly higher than that from the unaffected sheep. Oral administration of calcium sulfate prevented and cured the disease. We concluded that the disease of Guizhou semi-fine wool sheep in the Weining County is due to S deficiency caused by the high Fe in forages.

关键词： Guizhou semi-fine wool sheep sulfur iron calcium sulfate wool-eating

肺保护性通气联合围手术期呼吸功能锻炼对老年衰弱结直肠癌手术患者预后的影响

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中国现代医学杂志 2025年第4期35卷 91-96页

作者：颜梅申笑笑刘迪杨勇内江市第一人民医院麻醉科四川内江641099 铜川市人民医院麻醉科陕西铜川727100

目的探讨肺保护性通气联合围手术期呼吸功能锻炼对老年衰弱结直肠癌手术患者预后的影响。方法选取2021年1月—2023年6月在内江市第一人民医院就诊的92例老年衰弱结直肠癌手术患者,按摸球法分为对照组和实验组,每组46例。对照组接受常规... 详细信息

目的探讨肺保护性通气联合围手术期呼吸功能锻炼对老年衰弱结直肠癌手术患者预后的影响。方法选取2021年1月—2023年6月在内江市第一人民医院就诊的92例老年衰弱结直肠癌手术患者,按摸球法分为对照组和实验组,每组46例。对照组接受常规通气模式,实验组接受肺保护性通气联合围手术期呼吸功能锻炼。比较两组患者在气腹前(T_(1))、气腹1 h(T_(2))、拔管前(T_(3))的呼吸力学指标[气道峰压(Ppeak)、平均气道压(Pmean)、肺顺应性(CL)],在麻醉诱导前(T_(0))、T_(2)、气管导管拔除后10 min(T_(4))的氧合指标[脉搏血氧饱和度(SpO_(2))、动脉氧分压(PaO_(2))、肺泡动脉血氧分压差[P(A-a)DO_(2)]]的变化,比较两组患者血清肺表面活性蛋白质A(SP-A)水平、St George's呼吸疾病问卷评估量表(SGRQ)评分、术后肺部并发症(肺炎、低氧血症、呼吸衰竭、肺不张、肺栓塞)的状况。结果两组患者T_(1)、T_(2)、T_(3)的Ppeak、Pmean和CL水平比较,结果:(1)不同时间点Ppeak、Pmean和CL水平比较,差异均有统计学意义(P0.05),两组患者CL水平变化趋势比较,差异有统计学意义(P0.05),两组患者P(A-a)DO_(2)变化趋势比较,差异有统计学意义(P<0.05)。两组患者术前、术后1和7 d SP-A水平比较,结果:(1)不同时间SP-A水平比较,差异有统计学意义(P<0.05);(2)两组患者SP-A水平比较,差异有统计学意义(P<0.05),实验组在术后1 d和术后7 d的SP-A水平均低于对照组;(3)两组患者SP-A水平变化趋势比较,差异有统计学意义(P<0.05)。实验组治疗前后症状、活动能力和疾病影响的评分的差值均高于对照组(P<0.05)。实验组并发症总发生率低于对照组(P<0.05)。结论肺保护性通气联合围手术期呼吸功能锻炼能有效降低老年衰弱结直肠癌术后患者的肺部并发症发生率,改善呼吸力学和氧合指标,提升患者术后生活质量,对于这类患者的围手术期管理具有重要价值。

关键词：结直肠癌肺保护性通气围手术期呼吸功能锻炼老年衰弱并发症

Sulfur-Induced Copper Deficiency in the Yaks

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Agricultural Sciences in China 2009年第8期8卷 1000-1003页

作者： shen xiao-yun Department of Biology Chongqing University of Science and Technology Chongqing 401331 PR. China Key Laboratory of Animal Ecology and Conservation Biology Institute of Zoology Chinese Academy of Sciences Beijing 100101P.R. China

Since the 1990s, yak in the Haizi area in China has been affected by an ailment characterized by pica, emaciation, dyskinesia, and anemia. To determine the cause of disease, the mineral composition of soil and forages, and samples of blood, hair, and liver of yaks from the Haizi area in China were determined. The concentrations of copper in soil and forage from affected ranches and unaffected areas are within the normal ranges. The mean concentration of copper in blood and liver from the affected yaks was （0.31±0.03） and （13.7±3.1）μg·g^-1 respectively, compared with （0.98±0.16） and （95.6±11.2）μg·g^-1 for unaffected yaks. The concentrations of sulfur in soil and forage from affected ranches were （1.91±0.26） and （1.37±0.17）%, respectively, compared with （1.11±0.31） and （0.52±0.18）% （dry matter） for normal areas. The contents of sulfur in blood and liver affected animals were （7.32±1.8） and （2.54±3.1）%, respectively, compared with （4.22±0.73） and （1.31±0.33）% （in fresh and soft tissues） for healthy animals, respectively. Oral administration of tribasic copper chloride prevented and cured the disease. Thus it is reasonable to conclude that ailments of yaks in the Haizi area are probably caused by a secondary copper deficiency, mainly due to high sulfur content in soil and forage.

关键词： yak sulfur copper nutrition disease

Bioinspired and biomimetic membranes for water purification and chemical separation: A review

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Frontiers of Environmental Science & Engineering 2021年第6期15卷 141-173页

作者： Elham Abaie Limeimei Xu Yue-xiao shen Department of Construction Civil and Environmental EngineeringTexas Tech UniversityLubbockTX 79409USA

Bioinspired and biomimetic membranes that contain biological transport channels or attain their structural designs from biological systems have been through a remarkable development over the last two *** take advantage of the exceptional transport properties of those channels,thus possess both high permeability and selectivity,and have emerged as a promising solution to existing *** the discovery of biological water channel proteins aquaporins(AQPs),extensive efforts have been made to utilize them to make separation membranes–AQP-based membranes,which have been *** exploration of AQPs’unique structures and transport properties has resulted in the evolution of biomimetic separation materials from protein-based to artificial channelbased ***,large-scale,defect-free biomimetic membranes are not available *** paper reviews the state-of-the-art biomimetic membranes and summarizes the latest research progress,platform,and *** it critically discusses the potential routes of this emerging area toward scalable *** conclude that an appropriate combination of bioinspired concepts and molecular engineering with mature polymer industry may lead to scalable polymeric membranes with intrinsic selective channels,which will gain the merit of both desired selectivity and scalability.

关键词： Aquaporins Artificial water channels Biomimetic membranes Chemical separation and water purification