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151.
The photophysical and photochemical properties of tetraaminophthalocyanine complexes of lutetium and zinc covalently linked to polyacrylic acid were studied alongside those of unsubstituted zinc phthalocyanine within the same polymeric fiber matrix. All three phthalocyanines within the solid fiber matrices showed photoactivity by the generation of singlet oxygen as was observed in solution. The fluorescence behaviors of the composite fibers equally parallel those in solution. For the unsubstituted zinc phthalocyanine composite, the fiber showed fluorescence quenching on interaction with gaseous nitrogen dioxide similar to that in DMF and, thus could be a promising nanofabric material in developing optoelectronic devices that are responsive to the gas. 相似文献
152.
Zinc ion (Zn2+) is an important and a most useful biological trace nutrient responsible for the activity of several enzymes. Zn2+ concentrations in the environment as well as in the human body increase beyond permissible limits as a consequence of its mining and widespread industrial applications. Such excess Zn2+ concentrations are toxic to humans and many aquatic organisms. The magnetic inertness and spin paired electronic configuration of Zn2+ makes it hard to detect by common analytical techniques. Therefore, fluorometric detection using chemosensor is the most effective tool for the environmental and biological detection of Zn2+. We have developed a novel pyridine-constrained bis(triazole-linked hydroxyquinoline) ligand as a reversible fluorescent chemosensor for Zn2+. The symmetrical ligand is highly selective for Zn2+ and fluoresces brightly upon complexation compared with other metal ions based on chelation-enhanced fluorescence mechanism. Interestingly, free ligand can be regenerated by treating the ligand–Zn2+ complex with aqueous ammonia. 相似文献
153.
Maryam Zarei 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):865-870
AbstractNovel derivatives of diethyl (4-oxo-2-phenylchroman-3-yl) methyl phosphonate have been synthesized under optimal conditions using domino-Knoevenagel-phospha-Michael reaction catalyzed by nano-zinc oxide. The combination of recovery and reusability of catalyst, simple and applicable approach, good reaction time and good yields of products make this method as a suitable route for this purpose. The structures of the products were determined by FT-IR, 1H-, 13C- and 31P- Nuclear Magnetic Resonance spectroscopies, and elemental analysis. 相似文献
154.
Shahla Mozaffari Marzieh Chaloosi Faten Divsar Ebrahim Abouzari-Lotf Samad T Bavili Ali Yousefi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2439-2448
The complexation reactions between 7,10,13-triaza-1-thia-4,16-dioxa-20,24-dimethyl-2,3;17,18-dibenzo-cyclooctadecane-6,14-dione ( TTD ) and 7,10,13-triaza-1-sulfoxo-4,16-dioxa-20,24-dimethyl-2,3;17,18-dibenzo-cyclooctadecane-6,14-dione ( TSD ) macrocycles with Ag+, Cd2+, Cu2+, Pb2+, Sr2+, Tl+, and Zn2+ ions have been studied in ethanol and methanol solutions at 25°C. The complexes formed between macrocycles ( TTD ) and ( TSD ) with these metals cations had a stiochiometry of 1:1 and 1:2, respectively. The stability constants of the resulting complexes were determined and found to decrease in the order Cu2+ > Zn2+ > Ag+ > Tl+ > Cd2+ > Pb2+ > Sr2+ with macrocycle ( TTD ) and Tl+ > Zn2+ > Cd2+ > Pb2+ > Cu2+ > Ag+ > Sr2+ with macrocycle ( TSD ). 相似文献
155.
A. Müller E. Krickemeyer F. El-Katri D. Rehder A. Stammler H. Bgge F. Hellweg 《无机化学与普通化学杂志》1995,621(7):1160-1170
Simple Trithio- and Perthiocarbonato Complexes with Interesting Bond Properties: [E(CS3)2]2? (E = Sn, Zn, Cd), [E(CS3)3]3? (E = As, Sb, Bi, Co), {Cu(CS3)?}∞ and [Zn(CS4)2]2? By reactions of potassium trithiocarbonate ( 1 ) with solutions of zinc(II)- acetylacetonate, cadmium(II)-chloride, tin(II)-chloride, arsenic(III)-sulfide (suspension), antimony(III)-chloride, bismuth(III)-chloride and copper(II)-chloride in dimethyl sulfoxide, as well as of trisodium hexanitrito cobaltate(III) in water, and the precipitation of the complexes with an aqueous solution of tetraphenylphosphonium chloride the compounds (PPh4)2[Zn(CS3)2] ( 2 ), (PPh4)2[Cd(CS3)2] ( 3 ), (PPh4)2[Sn(CS3)2] ( 4 ), (PPh4)3[As(CS3)3] ( 5 ), (PPh4)3[Sb(CS3)3] ( 6 ), (PPh4)3[Bi(CS3)3] ( 7 ), (PPh4)3[Co(CS3)3] ( 8 ) and (PPh4)Cu(CS3) ( 9 ) have been isolated. (PPh4)2[Zn(CS4)2] · CH3NO2 ( 10 ) has been prepared by heating a solution of 2 in nitromethane to 60--70°C in presence of air. The reaction of 1 in dimethyl sulfoxide with an aqueous tetraphenylphosphonium chloride solution in presence of oxygen leads to (PPh4)2[C2S6] ( 11 ). The compounds have been characterized by spectroscopical studies (IR, Raman, UV/Vis, 113Cd/59Co-NMR), magnetic susceptibility measurements, powder diffractometry, elemental analyses and single crystal X-ray structure analysis ( 4 – 7 , 10 and 11 ). The difficult growing of single crystals has been reported in detail. For crystal data see Inhaltsübersicht. 相似文献
156.
Xylan is the major component of hemicellulose, which consists of up to one-third of the lignocellulosic biomass. When the
zinc chloride solution was used as a pretreatment agent to facilitate cellulose hydrolysis, hemicellulose was hydrolyzed during
the pretreatment stage. In this study, xylan was used as a model to study the hydrolysis of hemicellulose in zinc chloride
solution. The degradation of xylose that is released from xylan was reduced by the formation of zinc-xylose complex. The xylose
yield was >90% (w/w) at 70°C. The yield and rate of hydrolysis were a function of temperature and the concentration of zinc
chloride. The ratio of zinc chloride can be decreased from 9 to 1.3 (w/w). At this ratio, 76% of xylose yield was obtained.
When wheat straw was pretreated with a concentrated zinc chloride solution, the hemicellulose hydrolysate contained only xylose
and trace amounts of arabinose and oligosaccharides. With this approach, the hemicellulose hydrolysate can be separated from
cellulose residue, which would be hydrolyzed subsequently to glucose by acid or enzymes to produce glucose. This production
scheme provided a method to produce glucose and xylose in different streams, which can be fermented in separated fermenters. 相似文献
157.
盐酸溶液中氯代十六烷基吡啶在锌表面上的吸附及其缓蚀作用 总被引:4,自引:0,他引:4
盐酸溶液中氯代十六烷基吡啶在锌表面上的吸附及其缓蚀作用杨春芬,白宇新(云南大学化学系昆明650091)关键词锌,氯代十六烷基吡啶,吸附,缓蚀作用在抑制金属腐蚀的方法中,缓蚀剂的应用是最受重视的一种,因为它具有用量少,不需附加设备和不改变金属制品本性等... 相似文献
158.
锌和锡参与下末端环氧化物的选择性烯丙基化反应 总被引:1,自引:0,他引:1
烯丙基溴和金属辛或锡成功地将末端环氧化合物1一锅法合成高烯丙基醇2和双高烯丙基醇3. 还研究了环氧化合物取代基的影响, 并提出了此烯丙基化的反应途径 . 相似文献
159.
160.
Dr. Peng Wu Ting Zhao Yunfei Tian Dr. Lan Wu Prof. Dr. Xiandeng Hou 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(23):7473-7479
Proteins typically have nanoscale dimensions and multiple binding sites with inorganic ions, which facilitates the templated synthesis of nanoparticles to yield nanoparticle–protein hybrids with tailored functionality, water solubility, and tunable frameworks with well‐defined structure. In this work, we report a protein‐templated synthesis of Mn‐doped ZnS quantum dots (QDs) by exploring bovine serum albumin (BSA) as the template. The obtained Mn‐doped ZnS QDs give phosphorescence emission centered at 590 nm, with a decay time of about 1.9 ms. A dual‐channel sensing system for two different proteins was developed through integration of the optical responses (phosphorescence emission and resonant light scattering (RLS)) of Mn‐doped ZnS QDs and recognition of them by surface BSA phosphorescent sensing of trypsin and RLS sensing of lysozyme. Trypsin can digest BSA and remove BSA from the surface of Mn‐doped ZnS QDs, thus quenching the phosphorescence of QDs, whereas lysozyme can assemble with BSA to lead to aggregation of QDs and enhanced RLS intensity. The detection limits for trypsin and lysozyme were 40 and 3 nM , respectively. The selectivity of the respective channel for trypsin and lysozyme was evaluated with a series of other proteins. Unlike other protein sensors based on nanobioconjugates, the proposed dual‐channel sensor employs only one type of QDs but can detect two different proteins. Further, we found the RLS of QDs can also be useful for studying the BSA–lysozyme binding stoichiometry, which has not been reported in the literature. These successful biosensor applications clearly demonstrate that BSA not only serves as a template for growth of Mn‐doped ZnS QDs, but also impacts the QDs for selective recognition of analyte proteins. 相似文献