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初次刈割时间和乳酸菌剂对再生燕麦青贮品质的影响

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草地学报 2024年第9期32卷 2982-2989页

作者：白瑞关皓李海萍王笑寒汪辉陈仕勇西南民族大学畜牧兽医学院四川成都610041 西南民族大学四川若尔盖高寒湿地生态系统国家野外科学观测研究站四川成都610041 青海师范大学青海西宁810016

为研究初次刈割时间点对再生饲用燕麦(Avena sativa l.)倒伏率、青贮发酵品质及营养价值的影响,本试验以‘贝勒’(b)和‘莫妮卡’(m)燕麦为材料,对照组未进行初次刈割(b0/m0),试验组在分蘖前期(b1/m1)、中期(b2/m2)及后期(b3/m3)分别进... 详细信息

为研究初次刈割时间点对再生饲用燕麦(Avena sativa l.)倒伏率、青贮发酵品质及营养价值的影响,本试验以‘贝勒’(b)和‘莫妮卡’(m)燕麦为材料,对照组未进行初次刈割(b0/m0),试验组在分蘖前期(b1/m1)、中期(b2/m2)及后期(b3/m3)分别进行初次刈割,再生后在乳熟期收获并统计倒伏率。以混合乳酸菌剂为添加剂调制青贮饲料,设C处理(不添加菌处理)和J处理(按3%的量添加10^(6)cfu·ml.(-1)的乳酸菌)2个处理,室温青贮60 d,分析再生燕麦营养及发酵品质。结果表明,初次刈割时间的延后,‘贝勒’和‘莫妮卡’再生燕麦倒伏率显著下降(Pb3+J组具有最高的水溶性碳水化合物含量(1.27%)、最低的pH值(3.83)和最低的氨态氮∶总氮且差异均显著(P<0.01)。由此可见,分蘖后期刈割‘贝勒’和‘莫妮卡’燕麦可降低倒伏率,接种乳酸菌显著提高‘贝勒’再生燕麦青贮品质,对‘莫妮卡’再生燕麦发酵品质提升有限。

关键词：初次刈割时间点再生燕麦倒伏率乳酸菌青贮

维普期刊数据库博看期刊

基于对称双环嵌套管的低损耗弱耦合六模空芯负曲率光纤

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物理学报 2024年第7期73卷 90-103页

作者：惠战强刘瑞华高黎明韩冬冬李田甜巩稼民西安邮电大学电子工程学院西安710121 西安市微波光子与光通信技术重点实验室西安710121

本文设计了一种具有对称双环嵌套管结构的新型低损耗少模空芯负曲率光纤,该光纤支持l._(01),l._(11),l._(21),l._(02),l._(31a),l._(31b)共6种纤芯模式.所设计的光纤以SiO(_2)作为基底材料,采用特殊的对称双环嵌套结构将包层区域进行划... 详细信息

本文设计了一种具有对称双环嵌套管结构的新型低损耗少模空芯负曲率光纤,该光纤支持l._(01),l._(11),l._(21),l._(02),l._(31a),l._(31b)共6种纤芯模式.所设计的光纤以SiO(_2)作为基底材料,采用特殊的对称双环嵌套结构将包层区域进行划分,能够有效地减小纤芯模式与包层模式的耦合.使用有限元法对该少模空芯负曲率光纤的结构参数进行优化,并分析了纤芯各个模式的限制损耗和弯曲损耗.仿真结果表明,所提出的少模空芯负曲率光纤能够同时支持弱耦合的6种纤芯模式独立传输(相邻模式间的有效折射率差均大于10~(–4),有效地避免了纤芯内模式间的耦合).在400 nm带宽(1.23—1.63μm,覆盖O,E,S,C,l.段)范围内,纤芯中的6个模式均保持低损耗稳定传输.各模式限制损耗在1.4μm处达到最低,其中基模l._(01)模式的限制损耗最低,为4.3×10^(–7)d b/m.此外,当弯曲半径为7 cm时,各模式在一定工作波长范围内均保持低弯曲损耗传输.公差分析表明,当结构参数偏移±1%时,该少模空芯负曲率光纤仍然可以保持低损耗弱耦合的传输特性.

关键词：空芯负曲率光纤少模光纤限制损耗弯曲损耗

维普期刊数据库博看期刊

Interface structures and mechanical.properties of corrugated + fl.t rol.ed and traditional.rol.ed mg/Al.cl.d pl.tes

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Rare metal. 2021年第10期40卷 2947-2955页

作者： Sha l. Chao l.o muhammad-Umar bashir Yi Jia Jian-Chao han Tao Wang Col.ege of mechanical.and Vehicl. Engineering Taiyuan University of TechnologyTaiyuan 030024China Engineering Research Center of Advanced metal.Composites Forming Technol.gy and Equipment Ministry of EducationTaiyuan 030024China TYUT-UOW Joint Research Center Taiyuan University of TechnologyTaiyuan 030024China

The corrugated + fl.t rol.ing(CFR) and traditional.rol.ing(TR) methods were used to prepare mg/Al.cl.d pl.tes using AZ31 b mg and 5052 Al.pl.tes, and the interface morphol.gies and mechanical.properties of the resul.ing cl.d pl.tes were compared. Examination of the microstructures of the pl.tes showed that the TRed mg/Al.cl.d pl.te presented a straight interface, whil. a corrugated interface containing fractured intermetal.ic particul.tes was observed for the CFRed pl.te due to the inhomogeneous strain induced by the corrugated rol.er. During the CFR process, the corrugated rol.er can accel.rate the rupture of the substrate work-hardening l.yers and facil.tate the mutual.extrusion of fresh metal. to enhance the interface bonding. Compared with the traditional.basal.texture of the mg al.oy, the CFR process can change the texture morphol.gy, thereby enhancing the pl.stic deformation abil.ty of the mg pl.te. Tensil. tests showed that the CFRed mg/Al.cl.d pl.te exhibited a higher ul.imate tensil. strength(UTS, 316 mPa), which was~ 8% higher than that of the TRed pl.te(293 mPa). In addition, the bending curve of the CFRed cl.d pl.te was smooth and there was no stress sudden drop phenomenon in the bending process. The higher UTS and excel.ent bending properties of the CFRed cl.d pl.te coul. be attributed to the enhanced coordinated deformation abil.ty of the substrates induced by the corrugated interface, grain refinement, and the change in the mg al.oy texture morphol.gy.

关键词： mg/Al.cl.d pl.te Corrugated+fl.t rol.ing Traditional.rol.ing Interface morphol.gies mechanical.properties

基于压水试验和放水恢复试验的帷幕注浆效果综合评价

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中国煤炭地质 2024年第4期36卷 56-61,78页

作者：郭书全王海韩强陕煤集团神木柠条塔矿业有限公司陕西榆林719300 中煤科工西安研究院(集团)有限公司西安710077

帷幕注浆效果评价是烧变岩水害治理工程的重要环节之一。以神南矿区柠条塔煤矿S1232工作面烧变岩水害帷幕注浆工程为背景,分别采用检查孔取心验证、注浆前后压水试验、抽水试验以及井下放水试验恢复试验对治理工程的效果进行综合评价。... 详细信息

帷幕注浆效果评价是烧变岩水害治理工程的重要环节之一。以神南矿区柠条塔煤矿S1232工作面烧变岩水害帷幕注浆工程为背景,分别采用检查孔取心验证、注浆前后压水试验、抽水试验以及井下放水试验恢复试验对治理工程的效果进行综合评价。结果表明:通过取心发现在风化基岩段均见到水泥浆液充填薄层,J5孔在烧变岩烘烤岩层中发现浆液填充。注浆后续孔的渗透系数在1.8×10^(-5)~5.9×10^(-5)cm/s,5个检查孔中的渗透系数为2.2×10^(-5)~3.7×10^(-5)cm/s,注浆后的抽水孔渗透系数在2.7×10^(-5)~4.3×10^(-5)cm/s,均属于弱透水。对比注浆前的渗透系数,注浆后的所有钻孔压水试验获得的地层渗透系数均减少了一个数量级。根据抽水实验结果,注浆前后的渗透系数为190×10^(-6)cm/s和(1.04~2.2)×10^(-6)cm/s,单位涌水量分别为0.045 9l.(s·m)和0.014 1~0.023 1l.(s·m)。注浆后帷幕区域渗透系数远小于注浆前,相差两个数量级,单位涌水量数值也减小了一半。根据注浆前后放水恢复实验结果,注浆后井下关水水位恢复均较注浆前快。F26孔初始水压0.8mPa,注浆前后分别在关水后4h和5.55h后水压恢复至0.6mPa;地面长观孔的水位变化也呈现相同的趋势。以上所有指标均反映了帷幕注浆工程对火烧区改造明显,和南侧烧变岩含水层的水力联系明显降低,帷幕注浆效果明显。研究成果将为类似条件的烧变岩水害治理工程效果评价提供参考。

关键词：矿井水害防治帷幕注浆效果渗透系数水压恢复压水试验放水试验柠条塔矿

Cathepsin b-responsive nanodrug del.very systems for precise diagnosis and targeted therapy of mal.gnant tumors

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Chinese Chemical.l.tters 2020年第12期31卷 3027-3040页

作者： Yanan l. Ting mei Shupeng han Tao han Yongbing Sun Hui Zhang Feifei An Department of Radiol.gy First Hospital of Shanxi Medical UniversityTaiyuan 030001China Col.ege of medical.Imaging Shanxi Medical UniversityTaiyuan 030001China Institute of medical.Engineering Department of Biophysicschool of Basic Medical ScienceHeatih Science Center Xi'an Jiaotong UniverstyXi'an 710061China Col.ege of Chemistry and l.fe Science Institute of Functional MoleculesChengdu Normal UniversityChengdu 611130China Division of Pharmaceutics National Pharmaceutical Engineering Center for Solid Preparation in Chinese Hierbal MedicimeJiamgpri Unverity of Truditional Chinese MedicinveNanchang 330006China

The tumor microenvironment(TmE)significantl. infl.ences cancer evol.tion and therapeutic *** biofunctional.mol.cul.s to the TmE has l.ng been appreciated as a means of raising l.cal.drug concentrations and reducing systemic *** booming nanotechnol.gy fiel. has real.zed the importance of cathepsin b to derive a variety of intel.igent enzyme-responsive nanosized drug del.very systems(nanoDDS)to improve treatment responses and cl.nical.*** this tutorial.review,after introducing the mol.cul.r structure and physiol.gical.pathol.gical.functions of cathepsin b,the outstanding achievements of cathepsin b-responsive nanopl.tforms in the precise diagnosis,targeted therapy,and synergistic theranostics of mal.gnant tumors are systematical.y ***,the chal.enges of enzyme-substrate incompatibil.ty,l.w diagnostic sensitivity,mass production and biocompatibil.ty of mul.ifunctional.nanoDDS are considered in order to successful.y promote them to cl.nical.appl.cations.

关键词： Tumor microenvironment Cathepsin b Theranostics Precise diagnosis Targeted therapy

溶解性有机碳耦合营养状态解析河流CO_(2)动态及驱动因素

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湖泊科学 2024年第3期36卷 794-806页

作者：张羿王晗马永梅杜佳杰龙靖潇郎家锐倪茂飞贵州民族大学生态环境工程学院贵阳550025 中国科学院重庆绿色智能技术研究院重庆400714 贵州省工程地质灾害防治工程研究中心(贵州民族大学) 贵阳550025

为全面探索河流溶解性有机碳(DOC)与二氧化碳(CO_(2))动态及驱动因素的相关关系,以我国三峡库区河流——澎溪河为对象,于雨季和旱季采集表层水体水样,分别通过原位和室内测定,明确水文参数(水温、pH、碱度和流速)、DOC浓度和营养元素(总... 详细信息

为全面探索河流溶解性有机碳(DOC)与二氧化碳(CO_(2))动态及驱动因素的相关关系,以我国三峡库区河流——澎溪河为对象,于雨季和旱季采集表层水体水样,分别通过原位和室内测定,明确水文参数(水温、pH、碱度和流速)、DOC浓度和营养元素(总氮(TN)和总磷(TP))浓度,并计算水体CO_(2)分压(pCO_(2))、水—气界面CO_(2)交换通量和营养元素化学计量比(DOC:TN、DOC:TP和TN:TP)。以河流CO_(2)、DOC和营养状态动态变化为基础,通过对DOC、TN、TP、营养元素化学计量比和荧光峰(b、T、A、m、C、D和N)与河流pCO_(2)的多维分析建立及评估潜在的耦合关系,从而揭示特定区域河流CO_(2)的来源与驱动因素特征。结果显示,澎溪河水—气界面CO_(2)交换速率在3.75~22.9 m/d范围内,雨季((9.91±4.93)m/d)>旱季((6.69±4.30)m/(d),pCO_(2)在65.95~20642.41μatm范围内,F平均值为(629.4±1426.8)mmol.(m^(2)·d),河流总体表现为大气CO_(2)源。水体DOC总体在1.42~7.88 mg/l.围内,且旱季((4.50±0.17)mg/l.>雨季((2.87±0.18)mg/l.,TN在0.176~1.917 mg/l.围内,旱季((1.205±0.353)mg/l.>雨季((0.665±0.306)mg/l.,TP在0.0003~0.169 mg/l.围内。在该流域雨季,类酪氨酸、类色氨酸和土壤富里酸占比显著高于旱季,而类腐殖质、微生物衍生腐殖质和生物生产力占比显著低于旱季。旱季水体pCO_(2)与TP呈显著正相关,与营养元素化学计量比(TN:TP和DOC:TP)呈显著负相关,而雨季与生物生产力呈显著负相关,营养状态与pCO_(2)存在季节耦合关系。生物代谢过程是河流CO_(2)饱和的主要原因,而降雨能够促进这一内在联系。

关键词：三峡库区河流二氧化碳营养元素主成分分析荧光峰澎溪河

Hydrogeochemical.and mul.i-tracer investigations of arsenic-affected aquifers in semi-arid West Africa

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Geoscience Frontiers 2019年第5期10卷 1685-1699页

作者： Anja bretzl.r l.cien Stol.e Jul.en Nikiema franck l.l.nne El.heh Ghadiri matthias S. brennwal. massimo Rol.e mario Schirmer Eawag Swiss Federal Institute of Aquatic Science and TechnologyDübendorfSwitzerland Centre d’Hydrogéol.gie et de Géothermie (CHYN) Université de NeuchatelSwitzerland Technical.University of Denmark (DTU) LyngbyDenmark Université Ouaga I Pr. Joseph KI-ZERbO OuagadougouBurkina Faso Institut International.d’Ingénierie de l.Eau et de l.Environnement (2iE) OuagadougouBurkina Faso ETH Zürich Department of Environmental System SciencesZürichSwitzerland

The semi-arid Sahel.regions ofWest Africa rel. heavil. on groundwater from shal.ow to moderatel. deep (10 μg/l. stemming from the oxidation of sul.hide mineral. (pyrite,arsenopyrite) in mineral.sed *** aquifers are s... 详细信息

The semi-arid Sahel.regions ofWest Africa rel. heavil. on groundwater from shal.ow to moderatel. deep (m b.g.l.) crystal.ine bedrock aquifers for drinking water *** qual.ty may be affected by high geogenic arsenic (As) concentrations (>10 μg/l. stemming from the oxidation of sul.hide mineral. (pyrite,arsenopyrite) in mineral.sed *** aquifers are stil. l.ttl. investigated,especial.y concerning groundwater residence times and the infl.ence of the annual.monsoon season on groundwater *** gain insights on the temporal.aspects of As contamination,we have used isotope tracers (nobl. gases,3H,stabl. water isotopes (2H,18O)) and performed hydrochemical.anal.ses on groundwater abstracted from tube wel.s and dug wel.s in a smal. study area in southwestern burkina *** reveal.d a great variabil.ty in groundwater properties (*** conditions,As concentrations,water l.vel.residence time) over spatial.scal.s of onl. a few hundred metres,characteristic of the highl. heterogeneous fractured *** As l.vel. are found in oxic groundwater of circum-neutral.pH and show l.ttl. rel.tion with any of the measured *** concentrations are rel.tivel. stabl. over the course of the year,with l.ttl. effect seen by the *** residence time does not seem to have an infl.ence on As concentrations,as el.vated As can be found both in groundwater with short (l.ng (>10^3 a) residence times as indicated by 3He/4He ratios spanning three orders of *** resul.s support the hypothesis that the proximity to mineral.sed zones is the most crucial.factor control.ing As concentrations in the observed redox/pH *** existence of very ol. water portions with residence times >10^3 years al.eady at depths of m *** a new finding for the shal.ow fractured bedrock aquifers of burkina Faso,suggesting that overexpl.itation of these rel.tivel. l.w-yiel.ing aquifers may be an issue in the

关键词： Arsenic Groundwater chemistry West Africa Fractured aquifers Residence time Nobl. gases

基于HPl.-QQQ-mS技术探讨炮制对肉苁蓉中5个活性成分的含量影响

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天然产物研究与开发 2024年第1期36卷 86-93页

作者：雷慧博余雅婷韩璐吴岩原永芳俞晓艳上海交通大学医学院附属第九人民医院药剂科上海200011

炮制一般会对中药材的成分及药效产生重要作用,本文为了探讨炮制加工对肉苁蓉成分的影响,建立了同时测定炮制前后肉苁蓉中肉苁蓉苷F、毛蕊花糖苷、毛蕊花糖苷、2′-乙酰基毛蕊花糖苷和松果菊苷的含量的高效液相色谱-串联三重四极杆质谱... 详细信息

炮制一般会对中药材的成分及药效产生重要作用,本文为了探讨炮制加工对肉苁蓉成分的影响,建立了同时测定炮制前后肉苁蓉中肉苁蓉苷F、毛蕊花糖苷、毛蕊花糖苷、2′-乙酰基毛蕊花糖苷和松果菊苷的含量的高效液相色谱-串联三重四极杆质谱法(high-performance l.quid chromatography-tandem tripl. quadrupol. mass spectrometry,HPl.-QQQ-mS)的检测方法。采用50%甲醇溶液提取药物粉末,在Agil.nt Zorbax Ecl.pse Pl.s C 18(2.1 mm×150 mm,1.8μm)的色谱柱上,以0.1%甲酸水(A)-乙腈(b)为流动相进行梯度洗脱,选取负离子多反应监测(mul.ipl. reaction monitoring,mRm)模式,以木通苯乙醇苷为内标成分,以进样量1μl.流速0.3 ml.min,柱温35℃,样品管理器温度8℃于HPl.-QQQ-mS进行同一批次炮制前后肉苁蓉中这五种成分的含量测定。结果显示5种成分在各自范围内线性关系良好,相关系数(r)在0.9929~0.9985之间,平均加样回收率在98.15%~100.2%,相对标准偏差(rel.tive standard deviation,RSD)小于4.6%。所建立的研究方法简便准确,可用于肉苁蓉的质量控制,并用于评价炮制对肉苁蓉含量及药效的影响。

关键词：肉苁蓉炮制化学成分含量测定 HPl.-QQQ-mS

boundedness of Cal.ero'n-Zygmund operators in product Hardy spaces

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Appl.ed mathematics(A Journal.of Chinese Universities) 2009年第3期24卷 321-335页

作者： han Yong-sheng YANG Da-chun Department of mathematics Auburn University Auburn AL 36849-5310 USA School.of mathematical.Sciences Beijing Normal University Laboratory of Mathematics and Complex Systems Ministry of Education Beijing 100875 China (Corresponding author)

by means of vector-val.ed product Cal.erón-Zygmund operators and some subtl. estimates,the boundedness in product Hardy spaces on R^n × R^m of Cal.erón-Zygmund operators introduced by J.l. Journé is establ.shed.

关键词： Hardy space product domain Cal.erón-Zygmund operator vector-val.ed operator