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Mechanical and durability properties of concrete containing nano-Cr2O3 and rice husk ash

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Mechanical and durability properties of concrete containing ...

TeIM2015第六届无机材料结构、性能及测试表征技术研讨会

作者： e.Mohseni M.A.Yazdi h.A.rBalgouri J.Yang Department of Civil engineering University of Guilan 上海交通大学

The present study investigates the compressive strength,flexural strength and water absorption of concrete specimens containing nano-CrO（NC）and rice husk ash（RhA）.Portland cement has been replaced by 10,20,and 30wt%RhA and then NC with the ratios of 1,2 and 3%of the weight of cement were *** durability properties of the produced samples were *** absorption was conducted to determine the durability properties of concrete *** results show that the presence of the nanoparticles enhanced the mechanical properties and durability of ***,the replacement of 1%RhA increased the mechanical properties of *** 1%,the mechanical properties of concrete samples was *** effect of RhA replacement on the water absorption is noticeable.

关键词： Mechanical and durability properties of concrete containing nano-Cr2O3 and rice husk ash

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华北平原夏玉米氮利用效率的遗传参数估计

中国农业大学学报 2007年第6期12卷 50-56页

作者：黎亮 C.Friedrich h.Longin 孙文涛 Albrecht e.Melchinger 陈绍江中国农业大学国家玉米改良中心霍恩海姆大学植物育种与种子科学及群体遗传学研究所德国斯图加特70593

为研究玉米品种氮利用效率相关性状的遗传参数,本试验选择20个具不同氮利用效率的单交种在华北平原的2个地点同期进行试验,氮肥处理设高氮(施氮,折合纯氮225 kg/hm2)和低氮(不施氮,其地块经过连续2年耕种使氮素耗竭)2个水平。试验结果表... 详细信息

为研究玉米品种氮利用效率相关性状的遗传参数,本试验选择20个具不同氮利用效率的单交种在华北平原的2个地点同期进行试验,氮肥处理设高氮(施氮,折合纯氮225 kg/hm2)和低氮(不施氮,其地块经过连续2年耕种使氮素耗竭)2个水平。试验结果表明,供试品种在低氮水平下的平均产量比高氮降低了22.6%,从8.45 t/hm2降低到6.45 t/hm2,穗粒数减少幅度较大为17.12%;而千粒重、出籽率、干物质含量、株穗率、籽粒含油率、籽粒蛋白质和淀粉含量在2个氮水平下的平均表现相近。2个试验点的联合方差分析表明,以上大部分籽粒性状的遗传方差在2个氮水平下均达到显著水平;所有性状的基因型×氮的互作方差都不显著。在2种氮水平下,籽粒淀粉含量与籽粒含油率及籽粒蛋白质含量间都表现出显著负相关,籽粒含油率与蛋白质含量表现出较弱的正相关。高氮和低氮水平下的产量表型相关系数为0.759,表明可以在高氮水平进行氮高效品种的筛选。

关键词：玉米杂交种产量氮利用效率遗传参数籽粒品质

Role of Sub-synoptic Variability of Soil Moisture in Seasonal Precipitation Variations

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Role of Sub-synoptic Variability of Soil Moisture in Seasona...

Do Observations during Patrolling Trips Detect Changes in Wildlife Presence & Diversity in National Parks?

第六次全国动力气象学术会议

作者： S.-h.Yoo K.e.Mitchell h.van den Dool R.W.higgins NOAA’s Climate Prediction Center Camp SpringsMDUSA NOAA’s environmental Modeling Center Camp SpringsMDUSA NOAA’s Climate Prediction Center Camp SpringsMDUSA NOAA’s Climate Prediction Center Camp SpringsMDUSA

＜正＞ In this study,the authors use the NCeP eta Regional Climate Model to investigate the impact of high-frequency variability of soil moisture on the variationsin warm-season mean *** focus on the influences of the diurnal cycleand synoptic variability of soil moisture,and target the ***-seasonprecipitation during the 1988 drought year and the 1993 flooding year. high-frequency variability of soil moisture enhances the daily variances ofprecipitation,temperature,and atmospheric *** the 1988 drought year,the

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Open Journal of ecology 2023年第11期13卷 794-805页

作者： Samir A. Koko Ahmed A. h. Siddig emad h. e. Yasin Nasradeen A. h. Gadallah Mohamed M. A. Adam Ahmed M. M. hasoba Ameer Awad Mohammed Faculty of Forestry University of Khartoum Khartoum North Sudan Faculty of Forestry University of Sopron Bajcsy-Zsilinszky utca 4 Sopron Hungary African Center of excellence on Climate Change Biodiversity and Sustainable Agriculture University Felix Houphouet-Boigny Abidjan C&#244te d’Ivoire Faculty of Forest Sciences and Technology University of Gezira Wad Madani Sudan Wildlife Research Center Khartoum North Sudan

Globally, mountains encompass spectacular landscapes and a great diversity of species. however, Savannah’s mountains in Sudan have been affected by the loss of diversity due to human activities and climate changes. Therefore, this study aims to assess changes in wildlife diversity in Jebel-eldair Nation Park (JeNP) based on only reports from patrolling activities, especially in the absence of regular wildlife monitoring programs. Reports of monthly wildlife observations during patrolling trips were used for the summer season in 2010 and 2018. Findings showed a moderate to high decline in the most important wildlife species (i.e. lion, wild dog, and crest porcupine). Six others are documented as rare species in reserve, including the civet, spotted hyena, striped hyena, jackal, seraval, and Siberian bird. Contrary and despite the diversity reduction, some species witnessed increases in their observation frequency, such as lesser kudu, caracal, monitor, and lunar bird. Moreover, human settlements, agricultural activities, and other anthropogenic factors were found to be the main drivers of biodiversity reduction in JeNP. The study recommends adopting this method to detect changes in wildlife communities, especially in a situation of deficiency and lack of funding to conduct regular monitoring programs.

关键词： Wildlife Monitoring Biodiversity Jebel-eldair Nature Reserve Patrolling Observations Savanna’s Mountain

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固定源废气中VOCs测定方法的研究及应用

化工环保 2024年第4期44卷 573-580页

作者：蔡美全丁萌萌周健楠常淼沈秀娥刘保献北京市生态环境监测中心大气颗粒物监测技术北京市重点实验室北京100048

采用固相吸附-热脱附/气相色谱-质谱法测定固定源废气中的挥发性有机物(VOCs),比较了低目标物含量(5~100 ng)和高目标物含量(50~1000 ng)时,内标法和外标法在定量分析时的差异,考察了气袋样品转移时间、内标物和替代物添加方式对测定结... 详细信息

采用固相吸附-热脱附/气相色谱-质谱法测定固定源废气中的挥发性有机物(VOCs),比较了低目标物含量(5~100 ng)和高目标物含量(50~1000 ng)时,内标法和外标法在定量分析时的差异,考察了气袋样品转移时间、内标物和替代物添加方式对测定结果的影响,分析了4类企业废气中VOCs的排放特征。结果表明,两种定量方式所绘制的校准曲线均满足国标hJ 734—2014中相关系数大于等于0.995的规定。当气样中正庚烷、乳酸乙酯、1-癸烯、1-十二烯含量较低时,更适合使用外标法测定;当气样中目标物含量较高时,测定前需优化热脱附条件,并用加标实验验证测定的准确性。气袋样品需在8 h内转移至吸附管中以延长保存时间。采用内标法时,在样品从气袋向吸附管转移前/后添加内标物和替代物,目标物测定偏差均小于30%。电子工业和汽车制造企业主要排放含氧VOCs,汽车维修企业以含氧VOCs和芳香烃为主,工业涂装企业主要为苯系物或含氧VOCs。

关键词：固定污染源废气挥发性有机物内标法外标法

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换热器设计与理论源典

换热器设计与理论源典

AN eXPeRIeNCe OF COMBINATION MANDIBULeCTOMY OPeRATION AS A TReATMeNT FOR ReeKLINGhAUSeN'S DISeASe ASSOCIATeD WITh SeVeRe FACIAL DeFORMITIeS

作者： N.h.·艾夫根(N.h. Afgan) e.U.·施林德尔(e.U. Schlunder)

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AN EXPERIENCE OF COMBINATION MANDIBULECTOMY OPERATION AS A T...

第二届中国国际暨第五届全国口腔颌面外科学术会议

作者： e．MORlTA h．IShII M．MTSUURA K．SeTO IST.DePT.OF OMFS SChOOL OF DeNTAL MeDICINe TSURUMI UNIV. YOKOhAMA JAPAN IST.DePT.OF OMFS SChOOL OF DeNTAL MeDICINe TSURUMI UNIV. YOKOhAMA JAPAN IST.DePT.OF OMFS SChOOL OF DeNTAL MeDICINe TSURUMI UNIV. YOKOhAMA JAPAN IST.DePT.OF OMFS SChOOL OF DeNTAL MeDICINe TSURUMI UNIV. YOKOhAMA JAPAN

Severe facial deformity that resulted from tumors of Reeklinghausen's disease is a rare complication of this disease. Recently,we had an experience of operating such a case,and achieved a good *** we take this opportu... 详细信息

关键词： AN eXPeRIeNCe OF COMBINATION MANDIBULeCTOMY OPeRATION AS A TReATMeNT FOR ReeKLINGhAUSeN'S DISeASe ASSOCIATeD WITh SeVeRe FACIAL DeFORMITIeS

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层状介质中三维物体重构的对比源反演算法

中国石油大学学报（自然科学版） 2007年第4期31卷 38-45页

作者：魏宝君 LIU Q h 中国石油大学物理科学与技术学院山东东营257061 Department of electrical&Computer engineering Duke University

对比源反演(CSI)算法将反演问题转化为求解成本泛函的极小值问题,从而形成重构对比源和对比度的迭代序列。开发了一种三维CSI算法对层状介质中的三维物体进行重构,该算法是对二维对比源反演算法的推广。该算法无须正演计算,亦无须人为... 详细信息

对比源反演(CSI)算法将反演问题转化为求解成本泛函的极小值问题,从而形成重构对比源和对比度的迭代序列。开发了一种三维CSI算法对层状介质中的三维物体进行重构,该算法是对二维对比源反演算法的推广。该算法无须正演计算,亦无须人为地选择正则化参数,反演过程更稳定。CSI的每一次迭代过程均采用快速Fourier变换技术计算并矢Green函数算子及其共轭算子,确保了该算法在三维层状介质情况下的高效率。复杂模型的反演结果说明,CSI算法对重构层状介质中的任意三维异常体是非常有效的。

关键词：对比源反演(CSI)算法层状介质三维物体重构并矢Green函数快速Fourier变换

Spray granulation of Fe and C nanoparticles and their impedance match for microwave absorption

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Journal of Materials Science & Technology 2018年第3期34卷 496-502页

作者： h.huang Y.Gao C.F.Fang A.M.Wu X.L.Dong B.S.Kim J.h.Byun G.F.Zhang D.Y.Zhou Key Laboratory of Materials Modification by Laser Ionand Electron Beams(Ministry of Education)School of Materials Science and EngineeringDalian University of TechnologyDalian116024China Composites Research Division Korea Institute of Materials Science797 Changwon-daeroSeongsan-guChangwonGyeongnam642-831Republic of Korea

The microwave absorbents of Fe and C nanoparticles as magnetic loss and dielectric loss material respectively were composited with the polyvinyl alcohol （PVA） as binder by spray granulation method, The electromagnetic parameters of Fe and C composite particles were analyzed by vector network. The complex permittivity and magnetic permeability of Fe and C composite particles matched well with increasing C nanoparticle content, and then the microwave loss property was improved. A minimum reflection loss （RL） of -42.7 dB at 3.68 Ghz for a composite with 4.6 mm in thickness can be obtained when the content ratio of the C nanoparticles, the modified Fe nanoparticles and the PVA is 21：49：30 （Sample 3）.

关键词： Dielectric loss Magnetic loss Spray granulation method Impedance match