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121.
Du Liping Ding Yuqing Prokop Aleš Tanner Robert D. 《Applied biochemistry and biotechnology》2001,91(1-9):387-404
Bubble size is a key variable for predicting the ability to separate and concentrate proteins in a foam fraction ation process.
It is used to characterize not only the bubble-specific interfacial a rea but also coalescence of bubbles in the foam phase.
This article describes the development of a photoelectric method for measuring the bubble size distribution in both bubble
and foam columns for concentrating proteins. The method uses a vacuum to withdraw a stream of gas-liquid dispersion from the
bubble or foam column through a capillary tube with a funnel-shaped inlet. The resulting sample bubble cylinders are detected,
and their lengths are calculated by using two pairs of infrared photoelectric sensors that are connected with a high-speed
data acquisition system controlled by a microcomputer. The bubble size distributions in the bubble column 12 and 1 cm below
the interface and in the foam phase 1 cm above the interface are obtained in a continuous foam fractionation process for concentrating
ovalbumin. The effects of certain operating conditions such as the feed protein concentration, superficial gas velocity, liquid
flow rate, and solution pH are investigated. The results may prove to be helpful in understanding the mechanisms controlling
the foam fractionation of proteins. 相似文献
122.
Johan Sjöblom Camilla Dagsgård Sébastien Simon Geir Sørland Morten Hana 《Journal of Dispersion Science and Technology》2017,38(2):206-215
The present study reports on the influence of partially hydrolyzed polyacrylamide (HPAM) on essential w/o emulsion properties. The characterization has been undertaken with low field NMR to follow droplet sizes and distributions, sedimentation and coalescence kinetic, bench-scale electrocoalescence (Ecrit) experiments to follow emulsion stability changes, and electrorheology to detect changes in the viscosity upon applying an external electric field. The result is that HPAM does not basically influence the droplet size distribution (DSD) and the stability level of the emulsions as can be expected of bulk polymers. However, there seems to be an interaction between added demulsifiers either through direct molecular interaction or via an interfacial complexation. 相似文献
123.
Djomice Beugre Sbastien Calvo Michel Crine Pierre Marchot 《Journal of Computational and Applied Mathematics》2010,234(7):2128-3752
In this paper a lattice Boltzmann method (LBM) is used to simulate isothermal incompressible flow in a RCM-NCX-1116 metallic foam. The computational technique is a multiple relaxation time (MRT) lattice Boltzmann equation model. Computer aided X-ray micro-tomography is used to obtain 3D images of the metallic foam, providing the geometry and information required for LB simulations of a single phase flow.Pressure drops are computed and successfully compared to experimental measures and correlated with Ergun’s equation. Invariance of Ergun’s parameters A and B with the sampling rate of the images is observed. 相似文献
124.
Based on our analysis of the hopcount of the shortest path between two arbitrary nodes in the class G
p
(N) of random graphs, the corresponding flooding time is investigated. The flooding time T
N
(p) is the minimum time needed to reach all other nodes from one node. We show that, after scaling, the flooding time T
N
(p) converges in distribution to the two-fold convolution (2*) of the Gumbel distribution function (z)=exp (–e
–z
), when the link density p
N
satisfies Np
N
/(log N)3 if N . 相似文献
125.
Y油田为缝洞型碳酸盐岩油藏,油藏复杂的地质特征决定了其开发模式有别于常规砂岩油藏.为了有效提高Y油田采收率,利用Eclipse数值模拟软件建立了地质模型,对水平井长度、射孔间距及酸压缝长等油藏产能影响因素与转注时机、注采比以及关井时间等注采参数进行了优化.结果认为:对于Y缝洞型碳酸盐岩油藏,水平井水平段长度为500m、射孔间距为20m或酸压规模为100m时,累计产油量可达到最大值;压力降至废弃压力时进行转注,可获得最大采收率;周期注采比等于1时,周期时效与累计增油量达到最大值;关井时间为8天时,采收率提高幅度最大. 相似文献
126.
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129.
深层高温油藏在开采过程中,由于近井地带压力变化剧烈,地层水蒸发致使结晶盐析出,进而导致储层孔隙度、渗透率降低.为研究稠油油藏高温盐析调剖的孔渗变化规律,根据盐类溶解/沉淀原理及储层孔隙度渗透率关系和填砂管模型高温盐析实验结果,建立了考虑地层水蒸发、水中氯化钠析出和储层孔渗变化的综合盐析模型.研究结果表明:随着堵剂注入量... 相似文献
130.
利用平台巴西圆盘加载方式和钢质压条加载方式,对两种厚度为25mm和50mm、不同密度的轻质泡沫混凝土(400~1000kg/m3)进行巴西圆盘劈裂试验,研究密度和厚度对泡沫混凝土裂纹宽度、劈裂强度、断裂韧度、断裂能的影响规律。结果表明,在橡胶垫平台巴西圆盘和钢质压条加载方式下,其劈裂断裂特征大致分为四个阶段:线性弹性段、非线性弹性段、起裂阶段、失稳阶段。同样加载率下最大裂纹宽度随着泡沫混凝土密度增加逐渐减小,劈裂拉伸强度、断裂韧度、断裂能呈幂函数形式增加。借鉴Reinhardt非线性软化曲线,对不同密度泡沫混凝土的应力软化关系进行曲线拟合,建立基于拉伸强度、断裂韧度等控制参数的应力-裂纹宽度关系三段式模型。基于试验结果,对理想多孔材料细观力学预测模型进行修正,获得泡沫混凝土孔隙率与拉伸强度的半经验公式。 相似文献