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Search Results: 1 - 10 of 75972 matches for " 高世菊 "
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扎鲁司特对低温诱发的肉鸡肺动脉高压的影响
欧德渊,乔健,刘文,杨鹰,范春艳,铭宇,
牲畜兽医学报 , 2005,
Abstract: ?将60只雄性艾维茵商品代肉鸡常规育雏,17日龄随机分为3组:常温对照组(常温组)、低温模型组(低温组)和低温扎鲁司特组(扎鲁司特组)。各组于处理后14d(31日龄)和21d(38日龄)分别用右心导管法及直接导管法测定扎鲁司特对肺动脉压(pap)和股动脉压(fap)的影响,同时测定红细胞压积(pcv)和腹水心脏指数(ahi)。结果:(1)在低温环境的早期,扎鲁司特使肉鸡肺动脉收缩压和舒张压均升高,后期仅使舒张压升高;(2)扎鲁司特使pcv升高,增加了血液黏性阻力;(3)扎鲁司特使ahi升高,促进右心肥大;(4)扎鲁司特对股动脉压无显著性影响。可见扎鲁司特促进了肉鸡肺动脉高压综合征的发生发展。
整治国土造福于民——论长江流域水土流失的严重性

生态学杂志 , 1983,
Abstract: ?
Fuzzy mathematical analysis of conservation tillage effect on yield based on Farmer Cognition
基于农户认知的保护性耕作模式产量效应模糊数学分析

汤秋香,谢瑞芝,李少昆,马林,林涛,石书兵,,刘国庆,胡震斌,牛兴奎
生态学报 , 2009,
Abstract: To evaluate effects of main conservation tillage methods on yield in various ecological regions. We analysed farmer cognitions of factors influencing yield under the main conservation tillage methods by interviewing peasant households in the Northeast China plain, North China plain, Chengdu plain and Northwest China oasis. The indexing set was determined from 7 yield parameters based on expert consultation and relevant literature. A comprehensive evaluation of conservation tillage methods in the various ecological regions was done using the fuzzy theory.The highest score of conservation tillage modes were wide and narrow spaced rotation planting that leaves a high stubble in the Northeast China plain, rotary tilled seeding of wheat under the bestrow of corn stalks and no-tillage seeding of corn and other crops under the bestrow of whole wheat stalks in the North China plain, no tillage with return of the high stubble in the Northwest China oasis and no\|tillage seeding of wheat and other crops under the bestrow of whole rice stalks in Chengdu plain.These research data should be a useful guide for the selection of conservation tillage method for optimum yield effect.
黑索金(RDX)对农作物毒性影响的初步研究
任莲,刘正蒙,沈立,沈志松,梁道荣,黄舜阶,崔如,学曾,
环境科学 , 1987,
Abstract: 黑索金(以下简称RDX),分子式为C3H6N6O6,学名环三亚甲基三硝胺,是一种威力大于梯恩梯(TNT)的烈性炸药。根据对哺乳动物和水生生物的毒理学试验,RDX是一种中等偏强的有毒物质。在我国,大多数RDX生产厂家排放的含有RDX废水被直接用来灌溉农田。迄今,尚未见到有关RDX对农作物影响的报道。我们早在1969年就开始用模拟的RDX废水对农作物进行毒性试验,探索RDX对农作物生长发育的影响,为制订工业废水灌溉农田的水质标准和安全使用废水提供科学依据。
基于农户认知的保护性耕作模式产量效应模糊数学分析
汤秋香?,谢瑞芝?,李少昆*?,马林?,林涛?,石书兵?,,刘国庆?,胡震斌?,牛兴奎?
生态学报 , 2009,
Abstract: 为了从产量角度评价不同生态区主体保护性耕作模式,以东北平原、华北平原、成都平原、西北绿洲区不同耕作模式为研究对象。经过专家咨询和相关文献分析,筛选确定7个因素作为保护性耕作影响产量的指标集,通过农户一对一调查,将农户对影响产量因素的认知作为基础数据,运用模糊综合评价方法对不同生态区主体保护性耕作模式进行评价。结果显示:不同生态区得分最高的模式分别为东北平原宽窄行留高茬交替休闲种植模式;华北平原上茬玉米秸秆还田+旋耕播种小麦,下茬小麦秸秆还田+免耕直播玉米模式;西北绿洲留高茬免耕直播模式;成都平原小麦或油菜或马铃薯等免耕+稻草覆盖模式。为选择各地具有产量优势的保护性耕作模式提供参考。
伦理视角下的知识经济
,董阳
科技进步与对策 , 2000,
Abstract: 初步分析了知识经济本身所具有的伦理意义,尤其是它对人们的思想道德、价值观念的积极引导作用。同时从高科技与伦理的关联作用,探讨了知识经济对伦理的依存。知识经济伦理关联
壳聚糖生姜大蒜提取物复合保鲜剂对草莓的保鲜效果

北方园艺 , 2012,
Abstract: 以草莓为材料,按壳聚糖8种浓度添加或不添加生姜大蒜提取液,构成0.5%~2.0%8个处理涂膜液,研究了室温条件下不同配比的壳聚糖与生姜大蒜提取物的复配涂膜液对果实的保鲜效果。结果表明处理7(1.5%壳聚糖添加生姜大蒜提取物)其4d腐烂指数最低,为1.110;贮藏期间对果实失重率抑制以处理3(1.5%壳聚糖溶液)与处理7和8(2.0%壳聚糖添加生姜大蒜提取物)的效果较为明显,分别为9.02%、6.94%、7.74%;对果实总糖和总酸含量、维生素C含量影响最小的是处理7。处理7对果实涂膜保鲜效果最好,该处理显著的抑制了果实腐烂指数和失重率的上升,延缓了果实总酸和维生素C含量的下降,且效果明显,优于其它各组处理。
鱼肉和鹅肉中氯霉素的比色适配体传感器快速检测

- , 2016, DOI: 10.13982/j.mfst.1673-9078.2016.5.047
Abstract: 本文提出了一种新颖的比色适配体传感器用于快速检测鱼肉和鹅肉中氯霉素(Chloramphenicol,CAP)。本方法的建立是基于核酸适配体特异性结合目标物的高选择性能和氧化钯纳米颗粒(PdO)标记聚合酶螯合物(EnVision,EV)的双重信号放大效应,它能特异性、灵敏性地快速检测样品中痕量氯霉素。EV上含有大约100个辣根过氧化物酶(Horseradish Peroxidase,HRP),它能够高效催化底物3,3',5,5'-四甲基联苯胺(TMB)产生颜色变化,并且PdO在一定程度上也能催化TMB出现蓝绿色,因此该方法可达到双重放大效果。同时,通过测定TMB吸光度的变化能对应计算真实样品中的氯霉素含量。结果表明,在最佳实验条件下,该方法具有较高的检测灵敏度并在0.02-150 ng/mL范围内具有良好的相关性,检测下限是0.01 ng/mL。此外,该方法已经成功地应用于分析鱼肉和鹅肉样品中的氯霉素,其结果与传统的酶联免疫吸附测定(ELISA)方法相一致。
A novel colorimetric aptasensor was developed for rapid identification of chloramphenicol (CAP) in fish and goose samples. The assay is based on a highly selective aptamer binding to its targets followed by a dual-amplification effect from large amounts of palladium oxide (PdO) nanoparticle labeled EnVision (EV). This method could detect ultra-trace amounts of CAP specifically, sensitively, and rapidly. EV has approximately 100 horseradish peroxidase (HRP) molecules and can effectively catalyze the substrate 3,3’,5,5’-tetramethylbenzidine (TMB) for color development. In addition, PdO can catalyze TMB to produce a blue-green color. Thus, a dual-amplification effect can be achieved by using the proposed method. The amount of CAP in samples can be calculated by measuring the change in the absorbance of TMB. The results indicate that, under optimal conditions, this method displays relatively high sensitivity and a good linear correlation with CAP concentration, within the range of 0.02~150 ng/mL. The lower detection limit was identified as 0.01 ng/mL. In addition, this assay was successfully used to analyze CAP concentrations in fish and goose samples, and the results were consistent with those obtained by the conventional ELISA method.
黑河中游取水总量控制风险管理研究
Risk Management of Total Water Withdrawal Control in the Middle of Heihe River Reach
 [PDF]

胡彩虹, , 吴泽宁, 管新建
Journal of Water Resources Research (JWRR) , 2012, DOI: 10.12677/JWRR.2012.16064
Abstract: 取水总量控制是通过取水量的合理分配和总量控制,实现流域经济社会和生态环境的协调发展。黑河是我国较早实施取水总量控制的流域之一,由于上游来水、区域取水以及用水等过程的不确定性,黑河中游取水总量控制系统不可避免存在着风险,有必要开展相应的风险管理研究。本文结合黑河中游实际情况,从黑河中游取水总量控制的风险因子出发,构建了黑河中游取水总量控制风险评价指标体系,并对风险进行了估算和分析。结果表明黑河中游的取水总量控制风险处于可控状态,但中游的农业和生态用水受到一定的限制。并辨识主要致险和承险因子,提出相应的风险管理措施,为取水总量控制在黑河中游的实施提供指导。
Total water withdrawal control is able to realize coordinated development of the social economic and ecological environment through the reasonable distribution and total amount control. The HeiheRiveris the early implementation of total water withdrawal control. Due to the uncertainty of flow runoff and water demand, the risk of total water withdrawal control in the middle of Heihe River reach is objectively exist, and the corresponding risk management research is also necessary. Based on the analysis of the risk factors, combining with the actual situation of the middle of Heihe river reach, the risk evaluation index system of total water withdrawal control was proposed and the risks were analyzed. The results show that the risk level of total water withdrawal control in the middle Heihe River reach is in a controllable state, but the agricultural and ecological water use are limited in certain extent. The main risk factors and counterforce factors are given which could provide guid- ance for risk management and implementation of total water amount control in this region.
陀螺仪漂移系数的多位置离心机标定方法及误差分析
Calibration Method and Error Analysis for Multi-Positional Method on Centrifuge of Gyroscope’s Drift Coefficients
 [PDF]

, 晓东
Dynamical Systems and Control (DSC) , 2016, DOI: 10.12677/DSC.2016.53008
Abstract:
为了准确标定陀螺仪漂移系数,本文在带反转平台的精密离心机上建立坐标系,并在考虑离心机误差源的情况下分析了坐标系间的位置关系。用齐次变换法推导出了陀螺仪各轴上精确的角速度输入并给出了比力输入标称值,再结合陀螺仪静态误差模型推导出含有陀螺仪漂移系数的各次谐波幅值表达式,通过离心机提供两种向心加速度获得陀螺仪各采样时刻的输出,应用谐波分析法可以求得各次谐波幅值大小,从而利用最小二乘估计对各漂移系数进行辨识。试验仿真表明采用带反转平台的离心机对陀螺仪漂移系数标定时可以有效的规避离心机误差,离心机误差只对于DI、DS和DOS的标定有影响,且影响非常大,须在考虑离心机误差的情况下才能够实现精确标定;对于其他系数标定没有影响。实际标定时需要精确测量反转平台回转轴与盘面的垂直度误差,反转平台回转轴倾角回转误差以及反转平台角速率与主轴角速率的大小之差等以满足标定精度要求。
In order to calibrate the drift coefficients of gyro precisely, in the paper, the coordinate systems on precision centrifuge with counter-rotating platform were established, and the positional relationships were analyzed in consideration of centrifuge errors. The accurate angular velocity along each axis of gyro was derived by using homogeneous transformation method and the nominal value of input specific force was given, and each harmonic amplitude expression containing drift coefficients of gyro was derived combining the static error model of gyro. The output at each sampling time of gyro was acquired by providing two centripetal accelerations on centrifuge, and each harmonic amplitude’s value was calculated by using harmonic analysis, thus each drift coefficient could be identified by least squire evaluation. The simulation results show that the method using the counter-rotating platform can avoid the centrifuge errors’ influences and the errors mainly impact on the DI, DS and Dos significantly which should be precisely calibrated in consideration of centrifuge errors; and the errors have no impacts on other coefficients. In real calibration, the perpendicularity between rotating axis of counter-rotating platform and the disk surface, the wobbles of rotating axis of counter-rotating platform and the difference between the angular rate of counter-rotating platform and the main axis should be measured precisely in order to meet the requirement.
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