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81.
82.
83.
Scalable Wet Deposition of Zeolite AEI with a High Degree of Preferred Crystal Orientation 下载免费PDF全文
Pei‐Sun Huang Chon Hei Lam Chien‐You Su Yen‐Ru Chen Prof. Dr. Wen‐Ya Lee Prof. Dr. Da‐Ming Wang Prof. Dr. Chi‐Chung Hua Prof. Dr. Dun‐Yen Kang 《Angewandte Chemie (International ed. in English)》2018,57(40):13271-13276
Producing zeolite films with controlled preferred orientation on an industrial scale is a long‐standing challenge. Herein we report on a scalable approach to the direct wet deposition of zeolite thin films and membranes while maintaining a high degree of control over the preferred crystal orientation. As a proof of concept, thin films comprising aluminophosphate zeolite AEI were cast on silicon wafer or porous alumina substrates. Electrical properties and separation performance of the zeolite thin films/membranes were engineered through controlling degree of preferred crystal orientation. 相似文献
84.
Berkant Kayan A.Murat Gizir Ferruh Erdogdu 《Reaction Kinetics and Catalysis Letters》2004,81(2):241-249
The rates of wet air oxidation of 2-nitrotoluidine and 2,4-dinitrotoluene in the presence of excess oxygen and at different
temperatures and oxygen pressures was investigated. Oxidation experiments were carried out at temperatures between 180 and
225oC and oxygen partial pressures of 1,0-3,0 MPa, in a 280 mL glass vessel-inserted stainless steel reactor. Copper sulfate (CuSO4 .5H2O) was used as a catalyst, and the effect of catalyst loading was studied by varying the concentration: 0.75, 2.5 and 25 mg/L
as Cu2+. Addition of Cu2+ ions in the reaction media accelerated 2-nitrotoluidine oxidation nearly ten times even if it exists in trace amount in the
reaction medium (0.75 ppm Cu2+). Unfortunately copper did not show catalytic effect for the oxidation of 2,4-dinitrotoluene.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
85.
Taylor F Mcaloon AJ Craig JC Yang P Wahjudi J Eckhoff SR 《Applied biochemistry and biotechnology》2001,94(1):41-49
The Quick-Germ process developed at the University of Illinois at Urbana-Champaign is a way to obtain corn oil, but with lower
capital costs than the traditional wet-milling process. Quick-Germ has the potential to increase the coproduct credits and
profitability of the existing dry-grind fuel ethanol process, but the fermentability of the corn remaining after oil recovery
has not been tested. Therefore, a series of pilot scale (50 L) fermentations was carefully controlled and monitored with unique
methods for standard inoculation and automatic sampling. It was found that the concentration of suspended solids was significantly
reduced in the Quick-Germ fermentations. When compared at the same concentration of fermentable sugars, the fermentation rate
and yield were not statistically different from controls. When Quick-Germ was integrated into a state-of-the-art dry-grind
fuel ethanol process, computer simulation and cost models indicated savings of approx $0.01/L of ethanol ($0.04/gal) with
the Quick-Germ process. Additional savings associated with the lower suspended solids could not be quantified and were not
included. However, the savings are sensitive to the price of corn oil.
Mention of brand or firm name does not constitute an endorsement by the U.S. Department of Agriculture over others of a similar
nature not mentioned. 相似文献
86.
ZrxCe1-xO2催化剂催化湿式氧化乙酸的活性研究 总被引:1,自引:0,他引:1
采用共沉淀法制备了ZrxCe1-xO2催化剂, 利用BET, XRD和XPS对其进行了表征, 并研究了催化剂催化湿式氧化乙酸的活性. 结果表明: Zr和Ce摩尔比为1∶9的催化剂催化湿式氧化乙酸时具有最好的活性, 当乙酸溶液的初始化学需氧量(COD)为5000 mg/L, 反应温度为230 ℃, 压力为5 MPa时, 120 min后, COD的去除率为76% . 催化剂具有良好的活性是因为在CeO2中加入Zr能够增大催化剂的比表面积和表面缺陷氧的含量, 并最终加快了HO2•自由基的产生, 从而提高了催化剂的活性. 相似文献
87.
Pretreatment of corn stover using wet oxidation to enhance enzymatic digestibility 总被引:17,自引:0,他引:17
Corn stover is an abundant, promising raw material for fuel ethanol production. Although it has a high cellulose content,
without pretreatment it resists enzymatic hydrolysis, like most lignocellulosic materials. Wet oxidation (water, oxygen, mild
alkali or acid, elevated temperature and pressure) was investigated to enhance the enzymatic digestibility of corn stover.
Six different combinations of reaction temperature, time, and pH were applied. The best conditions (60g/L of corn stover,
195°C, 15 min, 12 bar O2, 2 g/L of Na2CO3) increased the enzymatic conversion of corn stover four times, compared to untreated material. Under these conditions 60%
of hemicellulose and 30% of lignin were solubilized, whereas 90% of cellulose remained in the solid fraction. After 24-h hydrolysis
at 50°C using 25 filter paper units (FPU)/g of dry matter (DM) biomass, the achieved conversion of cellulose to glucose was
about 85%. Decreasing the hydrolysis temperature to 40°C increased hydrolysis time from 24 to 72 h. Decreasing the enzyme
loading to 5 FPU/g of DM biomass slightly decreased the enzymatic conversion from 83.4 to 71%. Thus, enzyme loading can be
reduced without significantly affecting the efficiency of hydrolysis, an important economical aspect. 相似文献
88.
Seiichiro Imamura Yo-ichi Taniguchi Yoshio Ikeda Saburo Hosokawa Hiroyoshi Kanai Hisanori Ando 《Reaction Kinetics and Catalysis Letters》2002,76(2):201-206
Three kinds of Ru/CeO2 catalysts were prepared. The mobility of the oxygen on Ru and their catalytic activity in the wet oxidation of acetic acid was investigated. Ru was present in the form of RuO2, and TPR experiment showed that the reaction, RuO2 + 2H2 Ru + 2H2O, took place in different temperature ranges depending upon the kind of the catalysts. The catalyst with easily reducible oxygen on Ru had high activity in wet oxidation, and the importance of the release of oxygen from Ru to the reactant was suggested. 相似文献
89.
CeO2-TiO2催化剂的表面结构及其湿式氧化活性 总被引:8,自引:0,他引:8
采用溶胶-凝胶法和共沉淀法制备了CeO2-TiO2催化剂,利用N2吸附、X射线衍射、透射电镜、X射线光电子能谱和Zeta电位分析等手段表征了催化剂的表面结构性质. 以乙酸和苯酚为目标物,进行了湿式氧化高浓度乙酸和苯酚的活性测试,研究了CeO2-TiO2催化剂表面结构与活性之间的关系. 结果表明, Ce和Ti之间的相互作用使复合氧化物CeO2-TiO2催化剂具有小的晶粒尺寸和高的比表面积,催化剂表面化学吸附氧含量增加,且不同制备方法得到的CeO2-TiO2催化剂表面电位点不同,共沉淀法制备的催化剂更有利于乙酸和苯酚的吸附. 在湿式氧化反应中, CeO2-TiO2催化剂有较高的活性,其中共沉淀法制备的催化剂活性最高; 在230 ℃, 5 MPa条件下反应120 min后,乙酸COD去除率为79%; 在150 ℃, 4 MPa下反应120 min后,苯酚COD去除率为96%. 相似文献
90.
Evidence is presented that all three theoretically predicted modes of phase separation take place in the ternary system polysulfone(PSf)/N,N-dimethyl acetamide(DMA)/water during the process of wet phase separation (WPS). The elementary process of solidification is reconsidered with regard to the (non-) equilibrium phase separation. Cast solutions with more than 15 wt% of PSf undergo nucleation and growth of the polymer lean phase with formation of separation membranes characterised by a cellular structure. When cast solutions with about 5-7 wt% of PSf undergo WPS, somewhere inside the ternary system conditions are established so that alongside other solidified PSf structures the bicontinuous spinodal structures superimposed by bead-like structures are also formed. Variety of lacy PSf structures with less/more polymer beads is the manifestation of the primary phase separation by the spinodal mode superimposed by the secondary phase separation taking place by heterogeneous nucleation and growth of the polymer rich phase mode. Latex formation during the WPS will also be explained. Skin formation on the cast solution - coagulation bath interface by direct accumulation of polymer is established regardless of the PSf content in the cast solution. 相似文献