全文获取类型
收费全文 | 53篇 |
免费 | 44篇 |
国内免费 | 71篇 |
专业分类
综合类 | 2篇 |
化学工业 | 118篇 |
金属工艺 | 25篇 |
矿业工程 | 6篇 |
石油天然气 | 2篇 |
一般工业技术 | 1篇 |
冶金工业 | 14篇 |
出版年
2013年 | 1篇 |
2008年 | 1篇 |
2006年 | 3篇 |
2005年 | 1篇 |
2004年 | 1篇 |
2003年 | 1篇 |
2002年 | 6篇 |
2001年 | 6篇 |
2000年 | 11篇 |
1999年 | 11篇 |
1998年 | 4篇 |
1997年 | 9篇 |
1996年 | 6篇 |
1995年 | 12篇 |
1994年 | 9篇 |
1993年 | 3篇 |
1992年 | 6篇 |
1991年 | 6篇 |
1990年 | 5篇 |
1989年 | 2篇 |
1988年 | 5篇 |
1987年 | 5篇 |
1986年 | 1篇 |
1985年 | 5篇 |
1984年 | 8篇 |
1983年 | 7篇 |
1982年 | 10篇 |
1981年 | 8篇 |
1980年 | 10篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1965年 | 1篇 |
1964年 | 2篇 |
排序方式: 共有168条查询结果,搜索用时 15 毫秒
1.
介绍了机械化学的概念和一些典型的反应及研究方法, 同时还扼要地阐述了机械化学在难选冶金属矿处理、粉体材料改性和有毒废弃物处理方面的应用及前景. 相似文献
2.
Numerical solution of viscous flow past a solid sphere with the control volume formulation 总被引:1,自引:0,他引:1
The control volume formulation with the QUICK finite difference scheme is used to solveincompressible liquid flow past a solid sphere in terms of stream function and vorticity.Several tech-nical points are addressed on improving the accuracy and efficiency of numerical simulation of similarproblems of fluid flow.In particular,the importance of suitable specification of the distortion func-tion to enforcing the far field boundarv conditions is emphasized. 相似文献
3.
STUDIES ON FLOODING POINT AND HOLD-UP IN A SOLVENT EXTRACTION COLUMN WITH RECIPROCATING SIEVE PLATES
The flooding point and hold-up of the dispersed phase in an extraction column with reciprocating-sieve plates of 32 mm inside diameter and 1960 mm effective column height have been investigated under thefollowing conditions:Percent perforation of the plates 40%,53.5% and 63.7%,diameters of perforatedholes 7.8,9.0 and 9.8 mm,and distances between plates 20 and 40 mm respectively.Experiments werecarried out with three different liquid-liquid systems covering a rather wide range of physical properties.The relative velocity of the two phases passing through the perforations of the plates is consideredin the present work to be related to the work done by the oscillating plates in the column on unit massof liquid in unit time.Therefore the flooding velocity and hold-up in extraction column with reci-procating sieve plates should be related to A~2F~3 instead of AF as reported before.Equations weredeveloped to correlate the experimental data of flooding point and hold-up respectively. 相似文献
4.
实验研究了使用阳离子表面活性剂Aliquat336与异辛烷构成的反胶团溶液,通过液-液萃取方式纯化工业级α-淀粉酶的过程.当使用的反胶团溶液组成为Aliquat336/isooctane/1%(V/V)n-butanol时,实验发现纯化工业级α-淀粉酶的最佳条件:水相组成为30mmol/L,pH10,或酶,萃取时间为1min;反萃液组成为30mmol/L,pH6,反萃时间为3min在此条件下,通过萃取循环能够达到纯化工业级α-淀粉酶的目的,经过一个萃取与反萃循环后,α-淀粉酶的比活提高1.5倍,酶活回收率达85%与此同时,工业级α-淀粉酶中所含的中性蛋白酶活回收率只有10%,而且其比活降低了近7倍。α-淀粉酶与中性蛋白酶间的分离系数能达10左右. 相似文献
5.
6.
Gas-liquid flow in simple systems consisting of capillaries is analyzed by theory of irreversible thermodynamics so as to shed light on induction of nonuniformity of multiphase flow. By the Prigogine's theorem of minimum entropy production, stability of uniform two-phase flow and possible transition to nonuniform distribution are discussed. The analysis of model systems suggests potential application of irreversible thermodynamics to research of multiphase hydrodynamics in chemical reactors. 相似文献
7.
测定了甲基环己烷-正庚烷-混合溶剂(环丁砜/苯甲醇及环丁砜/N-甲基-吡咯烷酮)体系在(35±0.1)和(45±0.1)C下的液液分层曲线及各体系的结线数据,并计算得到了混合溶剂的选择性、溶解度等数据.初步讨论了以上混合溶剂体系萃取分离甲基环己烷与正庚烷的基本性能.结果表明,同一温度下质量组成相同的环丁砜/苯甲醇混合溶剂体系的选择性、溶解度等均较环丁砜/N-甲基-吡咯烷酮混合溶剂体系为优.结合25C时的数据,考察了温度对这些溶剂体系的选择性、溶解度等的影响,表明升高温度能提高溶剂的溶解能力,而选择性则有所降低. 相似文献
8.
The phenomenon of hysteresis of contact angle is an important topic subject to a long time of argument.A simple hydrostatic model of sessile drops under the gravity in combination with an ideal surface roughness model is used to interpret the process of drop volume increase or decrease of a planar sessile drop and to shed light on the contact angle hysteresis and its relationship with the solid surface roughness. With this model, the advancing and receding contact angles are conceptually explained in terms of equilibrium contact angle and surface roughness only,without invoking the thermodynamic multiplicity. The model is found to be qualitatively consistent to experimental observations on contact angle hysteresis and it suggests a possible way to approach the hysteresis of three-dimensional sessile drops. 相似文献
9.
本文考察了表面活性添加剂对锌精矿加压氧化酸浸过程及元素硫行为的影响。研究了木质素磺酸钠在精矿、硫磺、浸渣表面的吸附和吸附的影响,考察了添加剂对熔硫的乳化作用,结合物理分析,对添加剂防止熔硫包裹精矿,进而改善锌精矿加压氧化酸浸过程的作用机理进行了探讨。得出了添加剂的合理用量。 相似文献
10.