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991.
Luis Bárzaga-Castellanos Ronald Neufert Bernd Markert 《The International Journal of Life Cycle Assessment》2001,6(4):231-242
The Life cycle inventory analysis (LCI) for the freight traffic with heavy duty vehicles in Germany was determined for the
reference year 1995 and the target year 2010 by application of ISO 14040 and ISO 14041. Based on these results and under consideration
of the dynamic development of road freight traffic with German heavy duty vehicles of >14 t max laden weight and composition
of the German heavy duty vehicles fleet in this class the LCI for the introduction of various scenarios for reducing emissions
from freight traffic was generated. Special emphasis was placed in the determination of the LCI for the implementation of
primary, secondary and a combination of primary and secondary emission reduction measures for heavy duty diesel engines such
as variation of diesel fuel characteristics, engine-based measures for exhaust gas optimisation, urea selective catalytic
reduction (SCR) process with and without fuel consumption optimised diesel engines and particulate trap for exhaust gas optimised
diesel engines with low sulphur diesel fuel. The overall environmental effects of the investigated measures on the other phases
of the product life cycle of the freight traffic with heavy duty vehicles and on associated and new products to be introduced
was included in the generated results for the LCI of each variant. For the implementation of the urea SCR process the results
are based on manufacturer data for the overall production process of SCR honeycomb catalysts and SCR application measurements
in engine and field test after a travelled distance of between 187,825 and 325,178 km under road traffic conditions with typical
EURO 2 standard diesel engines for heavy duty vehicles with a max laden weight of >32 t under control of and data certification
by TüV Automotive Bayern Sachsen GmbH.
Phase 2: Life Cycle Impact Assessment (DOI: http://dx.doi.Org/10.1065/ Ica2000.12.044.2) Phase 3: Life Cycle Interpretation
(DOI: http://dx.doi.orq/10.1065/ Ica2000.12.044.3) 相似文献
992.
5,6-Epoxycholestan-3beta-ol derivatives were hydrolyzed in a diastereoconvergent manner by growing and resting cells of several strains of Aspergillus niger, particularly A. niger ATCC 11394. These strains displayed opposite regioselectivity toward each isomer in an alpha and beta epoxide mixture, thus, the nucleophilic attack took place at the less substituted and the most substituted carbon atom on each diasteromer, respectively. These biocatalysts opened trisubstituted oxiranes but were unable to hydrolyze the disubstituted oxiranes in the tested sterol derivatives. These findings suggest that A. niger strains possess another hydrolytic ability different from the commercial A. niger epoxide hydrolase (EH) that did not accept this kind of steroidal oxiranes as substrates. 相似文献
993.
We discuss inference for data with repeated measurements at multiple levels. The motivating example is data with blood counts from cancer patients undergoing multiple cycles of chemotherapy, with days nested within cycles. Some inference questions relate to repeated measurements over days within cycle, while other questions are concerned with the dependence across cycles. When the desired inference relates to both levels of repetition, it becomes important to reflect the data structure in the model. We develop a semiparametric Bayesian modeling approach, restricting attention to two levels of repeated measurements. For the top-level longitudinal sampling model we use random effects to introduce the desired dependence across repeated measurements. We use a nonparametric prior for the random effects distribution. Inference about dependence across second-level repetition is implemented by the clustering implied in the nonparametric random effects model. Practical use of the model requires that the posterior distribution on the latent random effects be reasonably precise. 相似文献
994.
对EP系列经编人造血管的径向顺应性和纵向顺应性进行了体外测试和研究,并分析了不同制备工艺对经编人造血管的径向顺应性的影响。实验结果表明,紧密化处理和波纹化热定性对人造血管的径向顺应性影响较大。测试压力段的选择对人造血管成品的纵向顺应性有较大的关系。 相似文献
995.
996.
In a paper in this journal (Nouvellet et al., 2010), we presented results from experiments on the behaviour of the Pharaoh's ant, Monomorium pharaonis, along with a substantial statistical and theoretical analysis of the results. In a minor part of our paper, we compared our results with the related work of Richardson et al. (2010a). These authors have subsequently commented on our interpretation of their work (Richardson et al., 2011). In this Letter we respond to the comments of Richardson et al. (2011), and give detailed arguments why we stand by our original conclusions. 相似文献
997.
Moritz Ebeler Florian Pilgram Thomas Wellhfer Katrin Frankenfeld Matthias Franzreb 《Engineering in Life Science》2019,19(8):591-601
Magnetic separation processes are known as integrated bioanalytical protein purification method since decades and are well described. However, use of magnetic separation processes in a regulated industrial production environment has been prevented by the lack of suitable process equipment and prejudice against the productivity of the process and its qualification for cleaning‐in‐place operation. With the aim of overcoming this prejudice, a comprehensive process development approach is presented, based on a GMP‐compliant magnetic separator, including an optimization of the batch adsorption process, implementation into a technical‐scale, and the development and validation of cleaning routines for the device. By the implementation of a two‐step counter‐current binding process, it was possible to raise the yields of the magnetic separation process even for very low concentrated targets in a vast surplus of competing proteins, like the hormone equine chorionic gonadotropin in serum, from 74% to over 95%. For the validation of the cleaning process, a direct surface swabbing method combined with a total organic carbon analysis was established for the determination of two model contaminants. The cleanability of the process equipment was proven for both model contaminants by reliably meeting the 10 ppm criteria. 相似文献
998.
从观赏草观赏性出发,结合与适应性和生长繁殖相关的11个指标,通过层次分析法(AHP)对贵阳市引进的10个观赏草品种进行观赏适应性综合评价。结果表明,11个评价指标中,观赏草的株型、叶色、耐旱性所占权重均较大(>0.1),是影响其观赏适应性的重要指标;通过建立评分标准后,得出10个品种的观赏性排名为火焰狼尾草、花叶蒲苇、紫叶狼尾草、矮蒲苇、新西兰亚麻、金叶苔草、粉黛乱子草、蓝羊茅、红巨人朱蕉、黄金苔草;生长适应性排名为矮蒲苇、花叶蒲苇、火焰狼尾草、紫叶狼尾草、新西兰亚麻、黄金苔草、粉黛乱子草、金叶苔草、红巨人朱蕉、蓝羊茅;最终综合评分观赏适应价值极好的(Ⅰ级>4.30分)有花叶蒲苇、火焰狼尾草;观赏适应价值较好的(Ⅱ级3.56~4.30分)有矮蒲苇、紫叶狼尾草、新西兰亚麻、粉黛乱子草、金叶苔草;观赏适应价值一般的(Ⅲ级<3.56分)有蓝羊茅、红巨人朱蕉、黄金苔草。 相似文献
999.
We report the use of caprylic acid based impurity precipitation as (1) an alternative method to polishing chromatography techniques commonly used for monoclonal antibody purification and (2) an impurity reduction step prior to harvesting the bioreactor. This impurity reduction method was tested with protein A purified antibodies and with cell culture fluid. First, the operational parameters influencing precipitation of host cell proteins and high molecular weight aggregate in protein A pools were investigated. When used as a polishing step, the primary factor affecting purification and yield was determined to be pH. Caprylic acid precipitation was comparable to polishing IEX chromatography in reducing host cell protein and aggregate levels. A virus reduction study showed complete clearance of a model retrovirus during caprylic acid precipitation of protein A purified antibody. Caprylic acid mediated impurity precipitation in cell culture showed that the impurity clearance was generally insensitive to pH and caprylic acid concentration whereas yield was a function of caprylic acid concentration. Protein A purification of caprylic acid precipitated cell culture fluid generated less turbid product pool with reduced levels of host cell proteins and high molecular weight aggregate. The results of this study show caprylic acid precipitation to be an effective purification method that can be incorporated into a production facility with minimal cost as it utilizes existing tanks and process flow. Eliminating flow through chromatography polishing step can provide process intensification by avoiding the process tank volume constraints for high titer processes. Biotechnol. Bioeng. 2012; 109: 2589–2598. © 2012 Wiley Periodicals, Inc. 相似文献
1000.