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温度和热驯化对胡氏大生熊虫运动行为的影响 被引量:4
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作者 李晓晨 王立志 《动物学报》 SCIE CAS CSCD 北大核心 2005年第3期516-520,共5页
The beneficial acclimation hypothesis (BAH) predicts that animals acclimated to a particular temperature have enhanced performance or fitness at that temperature in comparison with animals acclimated to other temperat... The beneficial acclimation hypothesis (BAH) predicts that animals acclimated to a particular temperature have enhanced performance or fitness at that temperature in comparison with animals acclimated to other temperatures. The BAH has been tested by a variety of empirical examinations, and was rejected by some of them. In order to provide new evidences for the BAH, the effects of acute and acclimation temperature (AT) on locomotor performance of Macrobiotus hufelandi (Tardigrada: Macrobiotidae) were investigated. The tardigrades were collected from Nanwutai, Qinling Mountains which traverse from west to east in central China. The subjects were acclimated to either 2℃ or 22℃ for 2 weeks. The animal was transferred onto a frosted slide and allowed to walk freely at the performance temperature (PT) 2℃ or 22℃. Only one individual was tested per test bout, which lasted from three to five minutes. To avoid occurrence of thermal acclimation effect, the standard adaptation time was limited to 1.5 min. Each subject was tested for once at the same PT, and was tested only at one PT. A total of 25 individuals were tested and measured at the same PT. The locomotor performance of the animals was recorded with a digital video camera mounted on a microscope at 4×10 amplification and replayed on a PC. Every subject was identified. Walking speed (WS) and percentage of time moving (PTM) at both PTs (2℃ or 22℃) were selected as the rate parameters of locomotor performance. The two-way repeated measures ANOVA with a significance level of α= 0.05 and Duncan multiple range test were used to analyze the data. WS of the animals acclimated to and tested at the same temperatures was significantly faster than that for animals acclimated to and tested at the different temperatures, similarly, PTM of the animals acclimated to 22℃ and tested at 22℃ was significantly greater than PTM of animals acclimated to 22℃ and tested at 2℃, which indicated that the animals acclimated to a particular temperature have enhanced locomotor performance in that temperature relative to the animals acclimated to that temperature in other thermal environment. WS of the animals acclimated to 22℃ and tested at 22℃ was significantly faster than WS of animals acclimated to 2℃ and tested at 22℃, PTM of the animals acclimated to 22℃ and tested at 22℃ was significantly greater than PTM of animals acclimated to 2℃ and tested at 22℃. These results supported the BAH. It could be concluded that the PT and thermal acclimation as well as the interaction between the PT and AT significantly influence the locomotor performance of M.hufelandi, and that, despite the existence of a few results of this study that don’t support the BAH, some results of this study support for this hypothesis, and that the animals acclimated to a particular temperature have enhanced locomotor performance in that temperature relative to the animals acclimated to that temperature in other thermal environment, implying that any performance temperature that deviates from the acclimation temperature could cause the reduction of the walking speed which is closely related to the fitness of the M.hufelandi. 展开更多
关键词 standard performa multiple effects central digital speed with camera the was test time The SLIDE total video level range PTM east walk one at in new PTS be
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Augmenting the Heat Sink for Better Heat Dissipation
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作者 Mohammed H. S. Al Ashry 《Circuits and Systems》 2015年第2期21-29,共9页
Heat sinks were invented to absorb heat from an electronic circuit conduct, and then to dissipate or radiate this heat to the surrounding supposedly, ventilated space, at a rate equal to or faster than that of its bui... Heat sinks were invented to absorb heat from an electronic circuit conduct, and then to dissipate or radiate this heat to the surrounding supposedly, ventilated space, at a rate equal to or faster than that of its buildup. Ventilation was not initially recognized as an essential factor to thermal dispersion. However, as electronic circuit-boards continued to heat up, circuit failure became a problem, forcing the inclusion of miniaturized high speed fans. Later, heat sinks with fins and quiet fans were incorporated in most manufactured circuits. Now heat sinks come in the form of a fan with fans made to function as fins to disperse heat. Heat sinks absorb and radiate excess heat from circuit-boards in order to prolong the circuit’s life span. The higher the thermal conductivity of the material used the more efficient and effective the heat sink is. This paper is an attempt to theoretically design a heat sink with a temperature gradient lower than that of the circuit board’s excess heat. 展开更多
关键词 CONVECTIVE HEAT Transfer: HEAT Absorbed by the Natural AIR Flow Surrounding Hot Objects FORCED CONVECTIVE HEAT Transfer: Absorption of HEAT Using FORCED AIR Flow Conductivity: Is the ability of a System to Exchange or TRANSFER Temperature within a Body or MATERIAL through the Movement of Electrons MATERIAL That Does Not Conduct HEAT Is Considered a Nonconductor
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Preparation of Fluoroalkyl End-Capped Oligomer/Cyclodextrin Polymer Composites: Development of Fluorinated Composite Material Having a Higher Adsorption Ability toward Organic Molecules 被引量:1
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作者 Jun-Ichi Suzuki Yutaro Takegahara +2 位作者 Yuri Oikawa Yuta Aomi Hideo Sawada 《Journal of Encapsulation and Adsorption Sciences》 2018年第2期117-138,共22页
Fluoroalkyl end-capped vinyltrimethoxysilane oligomer [RF-(CH2CHSi(OMe)3)n-RF;RF = CF(CF3)OCF7, n = 2, 3;RF-(VM)n-RF] was applied to the preparation of fluoroalkyl end-capped vinyltrimethoxysilane oligomer/α-, β-, ... Fluoroalkyl end-capped vinyltrimethoxysilane oligomer [RF-(CH2CHSi(OMe)3)n-RF;RF = CF(CF3)OCF7, n = 2, 3;RF-(VM)n-RF] was applied to the preparation of fluoroalkyl end-capped vinyltrimethoxysilane oligomer/α-, β-, γ-cyclodextrin polymers (α-, β-, γ-CDPs) composites [RF-(VM-SiO2)n-RF/α-, β-, γ-CDPs] by the sol-gel reaction of the corresponding oligomer in the presence of the α-, β-, γ-CDPs under alkaline conditions. The RF-(VM-SiO2)n-RF/α-, β-, γ-CDPs composites thus obtained were found to give a good dispersibility toward the traditional organic media except for water, and were applied to the surface modification of glass to provide a sueperoleophilic/superhydrophobic characteristic on the modified surface, although the corresponding RF-(VM-SiO2)n-RF nanocomposites can give a usual oleophobic/superhydrophobic property on the surface. These composites powders were also found to be applicable to the packing material for the column chromatography to separate the mixture of oil/water and the water in oil (W/O) emulsions. More interestingly, these composite powders were found to have a higher adsorption ability toward not only low-molecular weight aromatic compounds such as bisphenol A and bisphenol AF but also volatile organic compounds, compared to that of the pristine α-, β-, γ-CDPs. 展开更多
关键词 FLUORINATED Oligomeric Composite CYCLODEXTRIN Polymer Surface Modification Superoleophilic Superhydrophobic Property Separation of Oil and Water Organic Molecule VOC ADSORPTION ability
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基于遗传算法和最小二乘支持向量机的织物剪切性能预测 被引量:2
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作者 卢桂馥 王勇 +1 位作者 窦易文 Gui-fu Yi-wen 《计量学报》 CSCD 北大核心 2009年第6期-,共4页
提出了一种基于最小二乘支持向量机的织物剪切性能预测模型,并且采用遗传算法进行最小二乘支持向量机的参数优化,将获得的样本进行归一化处理后,将其输入预测模型以得到预测结果.仿真结果表明,基于最小二乘支持向量机的预测模型比BP神... 提出了一种基于最小二乘支持向量机的织物剪切性能预测模型,并且采用遗传算法进行最小二乘支持向量机的参数优化,将获得的样本进行归一化处理后,将其输入预测模型以得到预测结果.仿真结果表明,基于最小二乘支持向量机的预测模型比BP神经网络和线性回归方法具有更高的精度和范化能力. Abstract: A new method is proposed to predict the fabric shearing property with least square support vector machines ( LS-SVM ). The genetic algorithm is investigated to select the parameters of LS-SVM models as a means of improving the LS- SVM prediction. After normalizing the sampling data, the sampling data are inputted into the model to gain the prediction result. The simulation results show the prediction model gives better forecasting accuracy and generalization ability than BP neural network and linear regression method. 展开更多
关键词 SUPPORT VECTOR MACHINES sampling data SUPPORT VECTOR MACHINES generalization ability simulation results linear regression genetic algorithm BP neural network prediction model 线 LS-SVM least square new method
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水稻强优势恢复系9311粒重的诱变改良 被引量:18
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作者 陈忠明 王秀娥 《分子植物育种》 CAS CSCD 2005年第3期353-356,共4页
通过EMS诱变恢复系9311种子筛选到了大粒突变体M316。M316整精米的粒长由原来的6.9mm增加到8.0mm,增幅达15.9%,千粒重由原来31g提高到35.6g,增幅达14.8%,但着粒密度明显变稀,由原来的6.77粒/cm减少到5.61粒/cm,减幅达17.1%,因此单株产... 通过EMS诱变恢复系9311种子筛选到了大粒突变体M316。M316整精米的粒长由原来的6.9mm增加到8.0mm,增幅达15.9%,千粒重由原来31g提高到35.6g,增幅达14.8%,但着粒密度明显变稀,由原来的6.77粒/cm减少到5.61粒/cm,减幅达17.1%,因此单株产量比原品种减产8.7%。并通过M2、M3、M4代该性状分离表现,初步推测该突变为隐性突变。有趣的是,该突变体与培矮64s、粤泰A、广占63s分别配制的F1,与原来组合两优培九、粤优938、丰两优1号相比,不仅千粒重有明显增加,穗长和每穗颖花数有不同程度提高,而着粒密度和其它主要性状未发生劣变,因而单株产量有不同程度提高。说明该突变体在粒重增加的同时,配合力得到显著改良。 展开更多
关键词 EMS 64s 广63S 938 1 9mm A cm
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不同日粮对奶牛瘤胃发酵模式及泌乳性能的影响 被引量:35
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作者 王吉峰 王加启 +3 位作者 李树聪 汪水平 姚美蓉 刘仕军 《畜牧兽医学报》 CAS CSCD 北大核心 2005年第6期569-573,共5页
选用4头安装永久瘤胃瘘管和十二指肠瘘管的泌乳奶牛(体重为483 kg±21 kg,泌乳日龄为175 d±6 d),研究4种日粮,分别为30∶70CW(粗料由羊草组成)、30∶70CCA(粗料为玉米青贮+苜蓿+羊草混合型)、50∶50CCA、65∶35CCA日粮对泌乳... 选用4头安装永久瘤胃瘘管和十二指肠瘘管的泌乳奶牛(体重为483 kg±21 kg,泌乳日龄为175 d±6 d),研究4种日粮,分别为30∶70CW(粗料由羊草组成)、30∶70CCA(粗料为玉米青贮+苜蓿+羊草混合型)、50∶50CCA、65∶35CCA日粮对泌乳奶牛瘤胃内pH、NH3 N浓度、VFA的动态变化及奶牛生产性能的影响。试验采用4×4拉丁方设计,每期23 d。结果表明,精粗比为65∶35CCA日粮条件下奶牛瘤胃内pH显著低于其它组(P<0 01), 65∶35CCA及50∶50CCA日粮组瘤胃内NH3 N浓度显著高于精粗比30∶70 日粮组(P<0 01),瘤胃内乙酸浓度随精料比例的提高而降低(P= 0 10),丙酸浓度、丁酸浓度及乙酸/丙酸比例差异均为极显著(P<0 01);在不同精粗比日粮条件下,乳脂率差异显著(P<0 01),以30∶70CCA组为最高;产奶量、乳蛋白率及非乳脂固形物含量均呈极显著差异(P<0 01),均以高精料组65∶35CCA组为最高。 展开更多
关键词 NH3-N VFA pH
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Investigation of Probability Generating Function in an Interdependent <i>M/M/</i>1:(∞;GD) Queueing Model with Controllable Arrival Rates Using Rouche’s Theorem
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作者 Vishwa Nath Maurya 《Open Journal of Optimization》 2012年第2期34-38,共5页
Present paper deals a M/M/1:(∞;GD) queueing model with interdependent controllable arrival and service rates where- in customers arrive in the system according to poisson distribution with two different arrivals rate... Present paper deals a M/M/1:(∞;GD) queueing model with interdependent controllable arrival and service rates where- in customers arrive in the system according to poisson distribution with two different arrivals rates-slower and faster as per controllable arrival policy. Keeping in view the general trend of interdependent arrival and service processes, it is presumed that random variables of arrival and service processes follow a bivariate poisson distribution and the server provides his services under general discipline of service rule in an infinitely large waiting space. In this paper, our central attention is to explore the probability generating functions using Rouche’s theorem in both cases of slower and faster arrival rates of the queueing model taken into consideration;which may be helpful for mathematicians and researchers for establishing significant performance measures of the model. Moreover, for the purpose of high-lighting the application aspect of our investigated result, very recently Maurya [1] has derived successfully the expected busy periods of the server in both cases of slower and faster arrival rates, which have also been presented by the end of this paper. 展开更多
关键词 Interdependent QUEUEING Model BIVARIATE Poisson Process Controllable Arrival Rates Probability Generating Function Laplace Transform Rouches THEOREM Performance Measures
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蜘蛛抗逆能力的研究 被引量:13
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作者 刘凤想 肖群支 +1 位作者 常瑾 赵敬钊 《蛛形学报》 2005年第1期42-46,共5页
本文对隐蛛科的白斑隐蛛;狼蛛科的拟环纹豹蛛、星豹蛛、真水狼蛛、细毛水狼蛛;卷叶蛛科的猫卷叶蛛;栅蛛科的栓栅蛛;球蛛科的温室希蛛;皿蛛科的草间钻头蛛、难波小黑蛛、隆背微蛛、花腹盖蛛;园蛛科的黄斑园蛛;管巢蛛科的棕管巢蛛;蟹蛛科... 本文对隐蛛科的白斑隐蛛;狼蛛科的拟环纹豹蛛、星豹蛛、真水狼蛛、细毛水狼蛛;卷叶蛛科的猫卷叶蛛;栅蛛科的栓栅蛛;球蛛科的温室希蛛;皿蛛科的草间钻头蛛、难波小黑蛛、隆背微蛛、花腹盖蛛;园蛛科的黄斑园蛛;管巢蛛科的棕管巢蛛;蟹蛛科的三突花蛛;跳蛛科的吉蚁蛛等10科共16种蜘蛛做了在30℃恒温条件下的抗逆能力测定。结果表明,蜘蛛是一类抗逆能力较强的动物,只要供给水分,其雌蛛的平均寿命在25d以上;水在蜘蛛生命活动中具有非常重要的作用,在相同的条件下,如果断食断水,蜘蛛的平均寿命显著缩短,只有6d左右;由于蜘蛛种类和生活环境的不同,其耐饥饿的能力也表现出很大的差异,一般地面活动的蜘蛛或靠水边活动的蜘蛛耐饥、耐水能力较差,而游猎性蜘蛛,尤其是结网的蜘蛛抗逆能力较强;雌蛛的抗逆能力大于雄蛛;三突花蛛的耐饥能力随着龄期的增加而加强。 展开更多
关键词 寿 饿
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温度对蜘蛛抗饥能力的影响 被引量:6
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作者 刘凤想 刘志诚 +1 位作者 常瑾 赵敬钊 《蛛形学报》 2005年第1期53-57,共5页
本文对隐蛛科的白斑隐蛛、狼蛛科的星豹蛛,栅蛛科的栓栅蛛,球蛛科的八斑鞘蛛,皿蛛科的花腹盖蛛,园蛛科的角类肥蛛,肖蛸科的鳞纹肖蛸,蟹蛛科的三突花蛛,管巢蛛科的粽管巢蛛,猫蛛科的斜纹猫蛛,跳蛛科的纵条蝇狮等11科11种蜘蛛的385头成蛛,... 本文对隐蛛科的白斑隐蛛、狼蛛科的星豹蛛,栅蛛科的栓栅蛛,球蛛科的八斑鞘蛛,皿蛛科的花腹盖蛛,园蛛科的角类肥蛛,肖蛸科的鳞纹肖蛸,蟹蛛科的三突花蛛,管巢蛛科的粽管巢蛛,猫蛛科的斜纹猫蛛,跳蛛科的纵条蝇狮等11科11种蜘蛛的385头成蛛,296头2龄幼蛛和126头亚成蛛共计807头蜘蛛分别在20℃、25℃、30℃和35℃4种恒温条件下作了的抗饥能力研究。结果显示:(1)实验蜘蛛的2龄幼蛛、亚成蛛和成蛛抗饥能力的大小与温度的高低呈负相关,即随着温度的升高,抗饥能力减小。(2)由于蜘蛛种类不同,其抗饥能力的大小也表现出很大的差异。无论是2龄幼蛛还是成蛛,均以花腹盖蛛和鳞纹肖蛸抗饥能力最差;2龄幼蛛抗饥能力最强的是角类肥蛛;成蛛抗饥能力最强的是栓栅蛛、白斑隐蛛和角类肥蛛。(3)同一种蜘蛛,由于发育阶段不同其抗饥能力也表现出很大差异,随着蜘蛛发育阶段增长,其抗饥能力加强。在本实验条件下所有蜘蛛都是以2龄幼蛛抗饥能力较差,亚成蛛次之,成蛛的抗饥能力最强。 展开更多
关键词 20
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低分子肝素/壳聚糖/海藻酸钠复合微囊的制备及释药性能 被引量:17
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作者 丘晓琳 李国明 叶俊生 《应用化学》 CAS CSCD 北大核心 2005年第4期361-366,共6页
以低分子肝素(LMWH)为囊芯,通过乳化分散成微囊核,然后依次用壳聚糖(CS)和海藻酸钠(ALG)通过大分子自组装形成多层结构的复合胶囊。IR和SEM测试技术对微囊进行的结构表征和形态观察表明,CS与LMWH、CS与ALG均以静电作用相结合。微囊球形... 以低分子肝素(LMWH)为囊芯,通过乳化分散成微囊核,然后依次用壳聚糖(CS)和海藻酸钠(ALG)通过大分子自组装形成多层结构的复合胶囊。IR和SEM测试技术对微囊进行的结构表征和形态观察表明,CS与LMWH、CS与ALG均以静电作用相结合。微囊球形规整,粒度分散性好,平均粒径为(6.9±0.85)μm。微囊对LMWH的包封率最高可达93.5%。微囊的体外药物释放实验表明,其半释放率的释放时间可长达72h。随CS浓度或ALG浓度的增大,药物释放速率减缓;释药速率随药物与壳聚糖质量比的增大而加快;交联度越高,微囊的释药速率越小;微囊在酸性条件下释药较快。 展开更多
关键词 ALG SEM CS
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Cyberspace Security Using Adversarial Learning and Conformal Prediction
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作者 Harry Wechsler 《Intelligent Information Management》 2015年第4期195-222,共28页
This paper advances new directions for cyber security using adversarial learning and conformal prediction in order to enhance network and computing services defenses against adaptive, malicious, persistent, and tactic... This paper advances new directions for cyber security using adversarial learning and conformal prediction in order to enhance network and computing services defenses against adaptive, malicious, persistent, and tactical offensive threats. Conformal prediction is the principled and unified adaptive and learning framework used to design, develop, and deploy a multi-faceted?self-managing defensive shield to detect, disrupt, and deny intrusive attacks, hostile and malicious behavior, and subterfuge. Conformal prediction leverages apparent relationships between immunity and intrusion detection using non-conformity measures characteristic of affinity, a typicality, and surprise, to recognize patterns and messages as friend or foe and to respond to them accordingly. The solutions proffered throughout are built around active learning, meta-reasoning, randomness, distributed semantics and stratification, and most important and above all around adaptive Oracles. The motivation for using conformal prediction and its immediate off-spring, those of semi-supervised learning and transduction, comes from them first and foremost supporting discriminative and non-parametric methods characteristic of principled demarcation using cohorts and sensitivity analysis to hedge on the prediction outcomes including negative selection, on one side, and providing credibility and confidence indices that assist meta-reasoning and information fusion. 展开更多
关键词 Active LEARNING Adversarial LEARNING Anomaly DETECTION Change DETECTION CONFORMAL PREDICTION Cyber Security Data Mining DENIAL and Deception Human Factors INSIDER Threats Intrusion DETECTION Meta-Reasoning Moving Target Defense Performance Evaluation Randomness Semi-Supervised LEARNING Sequence Analysis Statistical LEARNING Transduction
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Controlling Effects of Tight Reservoir Micropore Structures on Seepage Ability: A Case Study of the Upper Paleozoic of the Eastern Ordos Basin, China 被引量:4
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作者 YANG Bo QU Hongjun +4 位作者 PU Renhai TIAN Xiahe YANG Huan DONG Wenwu CHEN Yahui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第2期322-336,共15页
In this study, the types of micropores in a reservoir are analyzed using casting thin section(CTS) observation and scanning electron microscopy(SEM) experiments. The high-pressure mercury injection(HPMI) and constant-... In this study, the types of micropores in a reservoir are analyzed using casting thin section(CTS) observation and scanning electron microscopy(SEM) experiments. The high-pressure mercury injection(HPMI) and constant-rate mercury injection(CRMI) experiments are performed to study the micropore structure of the reservoir. Nuclear magnetic resonance(NMR), gas-water relative seepage, and gas-water two-phase displacement studies are performed to examine the seepage ability and parameters of the reservoir, and further analyses are done to confirm the controlling effects of reservoir micropore structures on seepage ability. The experimental results show that Benxi, Taiyuan, Shanxi, and Shihezi formations in the study area are typical ultra-low porosity and ultra-low permeability reservoirs. Owing to compaction and later diagenetic transformation, they contain few primary pores. Secondary pores are the main pore types of reservoirs in the study area. Six main types of secondary pores are: intergranular dissolved pores, intragranular dissolved pores, lithic dissolved pores, intercrystalline dissolved pores, micropores, and microfracture. The results show that reservoirs with small pore-throat radius, medium displacement pressure, and large differences in pore-throat structures are present in the study area. The four types of micropore structures observed are: lower displacement pressure and fine pores with medium-fine throats, low displacement pressure and fine micropores with fine throats, medium displacement pressure and micropores with micro-fine throats, and high displacement pressure and micropores with micro throats. The micropore structure is complex, and the reservoir seepage ability is poor in the study areas. The movable fluid saturation, range of the gas-water two-phase seepage zone, and displacement types are the three parameters that well represent the reservoir seepage ability. According to the characteristic parameters of microscopic pore structure and seepage characteristics, the reservoirs in the study area are classified into four types(Ⅰ–Ⅳ), and types Ⅰ, Ⅱ, and Ⅲ are the main types observed. From type Ⅰ to type Ⅳ, the displacement pressure increases, and the movable fluid saturation and gas-water two-phase seepage zone decrease, and the displacement type changes from the reticulation-uniform displacement to dendritic and snake like. 展开更多
关键词 micro-pore structure SEEPAGE ability movable fluid SATURATION the range of GAS-WATER two phase SEEPAGE zone DISPLACEMENT types
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A Knowledge-based System for the Analysis of the Ability of Paying back Loans 被引量:1
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作者 Zhu Ming(朱明) +1 位作者 Yang Baoan(杨保安) 《Journal of Donghua University(English Edition)》 EI CAS 2001年第1期123-126,共4页
This paper describes the development of a knowledgebased system (KBS) for determining whether or not, and under what conditions, a bank Ioan officer should grant a business loan to a company. The prototype system deve... This paper describes the development of a knowledgebased system (KBS) for determining whether or not, and under what conditions, a bank Ioan officer should grant a business loan to a company. The prototype system developed focuses on what is bank loans risks management, how to prevent risk by the analysis of the ability of paying back loans. The paper makes the structural analysis involved in the system's decision situation, the structured situation diagram or model, dependency diagram and the document needed by the KBS prototype system thus are developed. Through testing the samples from loan business, the quality for the analysis of the ability of paying back loans can be effectively evaluated by the KBS prototype system. 展开更多
关键词 KNOWLEDGE-BASED SYSTEM (KBS) the KBS prototype system the ability of paying BACK loans bank LOANS risk management.
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高效液相色谱-电喷雾离子阱质谱法鉴定金匮肾气丸总苷化学成分及代谢产物 被引量:10
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作者 李文兰 胡杨 +3 位作者 季宇彬 杜娟 孙志 白晶 《分析化学》 SCIE EI CAS CSCD 北大核心 2010年第12期1765-1770,共6页
应用高效液相色谱-电喷雾离子阱质谱法(HPLC-ESI/MSn)鉴定金匮肾气丸总苷的化学成分及总苷大鼠灌胃给药血浆化学成分或代谢产物。对比体内外样品色谱图各色谱峰,根据负离子模式下的分子离子峰获得化合物分子量信息,金匮肾气丸总苷含19... 应用高效液相色谱-电喷雾离子阱质谱法(HPLC-ESI/MSn)鉴定金匮肾气丸总苷的化学成分及总苷大鼠灌胃给药血浆化学成分或代谢产物。对比体内外样品色谱图各色谱峰,根据负离子模式下的分子离子峰获得化合物分子量信息,金匮肾气丸总苷含19个化学成分:没食子酰-3-O-芹糖基(1→6)葡糖苷、羟基芍药苷、莫诺苷、马钱苷、獐芽菜苷、地黄苷A或B、1,2,3-三-O-没食子酰葡萄糖、芍药苷、山茱萸新苷Ⅱ、6'-(3,4,5-三羟基苯甲酰)芍药苷、1,2,3,6-四-O-没食子酰葡萄糖、山茱萸新苷Ⅰ、五没食子酰葡萄糖、苯甲酰羟基芍药苷、丹皮酚原苷、苯甲酰芍药苷、4'-羟基,6'-(3,4,5-三羟基苯甲酰)芍药苷和两个未知化合物成分。金匮肾气丸总苷大鼠灌胃血浆鉴定出17个化学成分,其中有8个化合物以原型存在,9个可知代谢转化成分,分别为没食子酸,2-羟基苯乙酮-4-O-葡萄糖醛酸酯,芍药苷代谢素Ⅰ,2-羟基-4-甲氧基苯乙酮-5-O-硫酸酯,2,4-二羟基苯乙酮-5-O-硫酸酯,2,4-二羟基苯乙酮和3个未知成分。 展开更多
关键词 Ion Trap Mass SPECTROMETRY High Performance Liquid
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高效液相色谱法测定血浆中左亚叶酸钙的含量 被引量:6
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作者 邓富良 陈本美 +4 位作者 饶均明 周平 邓世林 陈新 余俊龙 《分析化学》 SCIE EI CAS CSCD 北大核心 2005年第7期996-998,共3页
建立了测定血浆中左亚叶酸钙含量的RPHPLC方法。采用DiamonsilC18色谱柱(150mm×4.6mm,5μm),乙腈50mmol/L磷酸氢二钾/磷酸二氢钾缓冲溶液(10∶90,V/V,用磷酸调pH至4.0)为流动相,用前经0.45μm的过滤膜,超声脱气,流速为1.0mL/min,... 建立了测定血浆中左亚叶酸钙含量的RPHPLC方法。采用DiamonsilC18色谱柱(150mm×4.6mm,5μm),乙腈50mmol/L磷酸氢二钾/磷酸二氢钾缓冲溶液(10∶90,V/V,用磷酸调pH至4.0)为流动相,用前经0.45μm的过滤膜,超声脱气,流速为1.0mL/min,紫外检测波长为290nm,柱温为35℃,进样量20μL。该方法最低检出限为0.2ng;线性范围为0.05~10mg/L,方法平均回收率在97.0%以上;日内及日间精密度的相对标准偏差分别小于4%和6%。该方法简单,快速,灵敏度高,重复性好。 展开更多
关键词 HPLC 线 6mm C18 min
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防卡润滑剂OCL-RQ的室内性能评价 被引量:3
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作者 周文欣 张建伟 +2 位作者 张佩 张克勤 赵俊峰 《钻井液与完井液》 CAS 北大核心 2005年第B05期32-33,120,共3页
为满足润滑剂的无荧光、无污染、抗温性好、易生物降解等要求,开展了防卡润滑剂OCL-RQ的研制。OCL-RQ润滑剂选用高效无毒(或低毒)、无荧光(或低荧光)的表面活性剂、矿物油等在一定温度下反应而成。在研制过程中重点从表面活性剂的HLB值... 为满足润滑剂的无荧光、无污染、抗温性好、易生物降解等要求,开展了防卡润滑剂OCL-RQ的研制。OCL-RQ润滑剂选用高效无毒(或低毒)、无荧光(或低荧光)的表面活性剂、矿物油等在一定温度下反应而成。在研制过程中重点从表面活性剂的HLB值、亲油基和亲水基的分布以及与油类的配伍性等方面进行了深入的研究,在此基础上又对其复配物的抗温性能和膜的强度进行了评价,并采用正交试验法对配方进行了优选。研制出的OCL-RQ润滑剂是一种淡黄色液体,加量为0.5%-2.0%时润滑系数降低率大于80%,能在钻头、钻具和其它工具的表面形成一层牢固的吸附膜,大幅度降低它们在钻进中的磨损,同时能够尽可能避免粘附卡钻事故;而且该剂具有一定的抗盐和降滤失作用,对钻井液性能基本无影响;原材料来源广,最终产品的价格合理,生产工艺简单。 展开更多
关键词 HLB
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HPLC法测定广西十个不同产地两面针中新棒状花椒酰胺的含量 被引量:17
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作者 刘绍华 覃青云 +3 位作者 唐献兰 方堃 杨卫豪 张祥民 《天然产物研究与开发》 CAS CSCD 2005年第3期337-339,共3页
分析并比较了广西十个不同产地的两面针中具有镇痛、抗炎和止血活性的新棒状花椒酰胺的含量。采用HPLC法,色谱柱为HYPERSILBDSC18,流动相为乙腈:水(50:50),流速为1.0mL/min,柱温40℃,检测波长268nm,进样量为20.0μL。发现不同产地的两... 分析并比较了广西十个不同产地的两面针中具有镇痛、抗炎和止血活性的新棒状花椒酰胺的含量。采用HPLC法,色谱柱为HYPERSILBDSC18,流动相为乙腈:水(50:50),流速为1.0mL/min,柱温40℃,检测波长268nm,进样量为20.0μL。发现不同产地的两面针中新棒状花椒酰胺的含量差别较大,金秀样品含量最高,为0.468%;桂林样品含量最低,为0.009%。本研究将为两面针在镇痛、抗炎和止血等方面的开发利用提供了可靠的科学依据,具有重要的应用前景。 展开更多
关键词 HPLC 广西 BDS C18 min
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用亲水性的C_(16)硅胶反相色谱柱分离测定血清样品中的雌激素 被引量:2
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作者 蔡亚岐 王玲 +4 位作者 梁立娜 刘京生 史亚利 牟世芬 江桂斌 《分析化学》 SCIE EI CAS CSCD 北大核心 2005年第7期913-916,共4页
将亲水性较强的C16硅胶反相色谱柱应用于血清样品中β雌二醇、雌三醇、雌酮和17α乙炔基雌二醇的分离。实验对分离条件进行了优化,得到的最佳色谱条件是:柱温40℃,流速1mL/min,以40%乙腈水溶液作等度洗脱。在此条件下4种雌激素可在大约2... 将亲水性较强的C16硅胶反相色谱柱应用于血清样品中β雌二醇、雌三醇、雌酮和17α乙炔基雌二醇的分离。实验对分离条件进行了优化,得到的最佳色谱条件是:柱温40℃,流速1mL/min,以40%乙腈水溶液作等度洗脱。在此条件下4种雌激素可在大约26min内实现基线分离,得到的4个色谱峰峰型对称。分离后的4种雌激素用紫外检测器在200nm处进行测定,方法对β雌二醇、雌三醇、雌酮和17α乙炔基雌二醇的检出限分别为0.024、0.015、0.012和0.016mg/L;校正曲线的线性范围为2~3个数量级,相关系数为0.998以上。方法应用于血清样品的测定,β雌二醇、雌三醇、雌酮和17α乙炔基雌二醇的标准加入回收率分别为96.3%、103.7%、100.1%和95.2%。 展开更多
关键词 17Α- 线 线 线 min
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高温环境对奶牛生理活动及生产性能的影响 被引量:75
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作者 魏学良 张家骅 +4 位作者 王豪举 晏梅 孙凤清 杨铭惠 尹思明 《中国农学通报》 CSCD 2005年第5期13-15,共3页
在2002-2003年对重庆市部分地方奶牛的生理活动、生产性能进行了监测,并对部分奶牛的血液生化指标进行了测定,结果表明:(1)在6-9月奶牛的直肠温度和呼吸频率显著高于3-5月和10-2月(P<0.05);(2)3-5月和10-2月的日平均泌乳量分别为(23.5&... 在2002-2003年对重庆市部分地方奶牛的生理活动、生产性能进行了监测,并对部分奶牛的血液生化指标进行了测定,结果表明:(1)在6-9月奶牛的直肠温度和呼吸频率显著高于3-5月和10-2月(P<0.05);(2)3-5月和10-2月的日平均泌乳量分别为(23.5±4.2)kg/d(n=31)、(22.1±5.3)kg/d(n=43),均高于6-9月高温时节的(7.6±5.1)g/d(n=52)(P<0.05),即在热应激期奶牛泌乳性能下降25.6%~33.5%;(3)热应激期的奶牛血清K+、Cl-、iCa+浓度显著升高(p<0.05),奶牛血清中总蛋白、白蛋白和球蛋白出现下降,碱性磷酸酶活性降低38.96%,α-淀粉酶降低8.52%,而谷丙转氨酶活升高3.47%;(4)在热应激期受胎率下降,繁殖疾病增加. 展开更多
关键词 2003 α- Cl^- K^%PLUS%
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助理护士专业能力培训的实践 被引量:8
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作者 毛俊 黎明 林书妆 《现代临床护理》 2005年第2期44-46,共3页
目的探讨岗前和岗位专业能力培训对助理护士专业能力的影响。方法将专业能力培训、岗前培训、试用期培训和岗位培训有机结合,采用讲座和示范方式,通过“演示—操作—纠正—再演示—再操作”循环教学法对助理护士专业能力进行培训。并在... 目的探讨岗前和岗位专业能力培训对助理护士专业能力的影响。方法将专业能力培训、岗前培训、试用期培训和岗位培训有机结合,采用讲座和示范方式,通过“演示—操作—纠正—再演示—再操作”循环教学法对助理护士专业能力进行培训。并在招聘考核、签约考核(培训3个月后)、续约考核(第一次签约后一年)测评助理护士专业能力。结果助理护士在续约考核与招聘考核专业能力成绩比较,经统计学分析,P<0.05,差异有统计学意义;全国护士执业考试合格率由培训前的95.2%上升到培训后的99.2%。结论有计划、有目标、有针对性地对助理护士进行岗前和岗位专业能力培训,可以帮助她们尽快地适应新的环境,实现从学生到专业护理人员的角色转变,以及从助理护士到注册护士的顺利过渡,提高助理护士的岗位适应能力,从而胜任临床护理工作。 展开更多
关键词 0.05
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