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131.
132.
Mikhael Pudovik Ludmila Kibardina Svetlana Terent'eva Arkady Pudovik 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract Reactions of chloromethylchlorophosphonates with heptamethyldisilazane(1 : 1 ratio]proceed with the formation of silylamidophosphonates, while with bis(chloromethy1)phosphinate P-N-P compounds were formed. 相似文献
133.
Shushanyan Artem D. Nikolaeva Nataliya S. Vikulova Evgeniia S. Zelenina Ludmila N. Trubin Sergey V. Sysoev Sergey V. Dorovskikh Svetlana I. Morozova Natalya B. 《Journal of Thermal Analysis and Calorimetry》2019,136(6):2341-2352
Journal of Thermal Analysis and Calorimetry - The volatile palladium(II) and copper(II) {O,N}-coordinated bis-chelate complexes of a new type, Pd(dmht)2 and Cu(dmht)2, where... 相似文献
134.
Oleksenko Ludmila Fedorenko George Maksymovych Nelly 《Research on Chemical Intermediates》2019,45(8):4101-4111
Research on Chemical Intermediates - Nanosized semiconductive Pd-containing sensor materials based on SnO2 were obtained by sol–gel technique. The highly sensitive gas sensor based on... 相似文献
135.
136.
Vasilisa V. Krasitskaya Natalia S. Goncharova Vladislav V. Biriukov Eugenia E. Bashmakova Marsel R. Kabilov Ivan K. Baykov Aleksey E. Sokolov Ludmila A. Frank 《Photochemistry and photobiology》2020,96(5):1041-1046
Bioluminescent solid-phase analysis was proposed to monitor the selection process and to determine binding characteristics of the aptamer–target complexes during design and development of the specific aptamers. The assay involves Ca2+-regulated photoprotein obelin as a simple, sensitive and fast reporter. Applicability and the prospects of the approach were exemplified by identification of DNA aptamers to cardiac troponin I, a highly specific early biomarker for acute myocardial infarction. Two structurally different aptamers specific to various epitopes of troponin I were obtained and then tested in a model bioluminescent assay. 相似文献
137.
Diastereoselective Synthesis of (Z)‐6‐(2‐Oxo‐1,2‐dihydro‐3H‐indol‐3‐ylidene)‐3,3a,9,9a‐tetrahydroimidazo[4,5‐e]thiazolo[3,2‐b]‐1,2,4‐triazin‐2,7(1H,6H)‐diones 下载免费PDF全文
Galina A. Gazieva Ekaterina A. Shishkova Ludmila B. Kulikova Natal'ya G. Kolotyrkina Natal'ya V. Sigay Angelina N. Kravchenko 《Journal of heterocyclic chemistry》2014,51(4):921-926
Two efficient and diastereoselective procedures for the synthesis of (Z)‐6‐(2‐oxo‐1,2‐dihydro‐3H‐indol‐3‐ylidene)‐3,3a,9,9a‐tetrahydroimidazo[4,5‐e]thiazolo[3,2‐b]‐1,2,4‐triazin‐2,7(1H,6H)‐diones by aldol‐crotonic condensation of 1,3‐dimethyl‐3a,9a‐diphenyl‐3,3a,9,9a‐tetrahydroimidazo[4,5‐e]thiazolo[3,2‐b]‐1,2,4‐triazin‐2,7(1H,6H)‐dione with isatins under acidic or basic catalysis are reported. Isomerization in (Z)‐7‐(1‐allyl‐2‐oxo‐1,2‐dihydro‐3H‐indol‐3‐ylidene)‐1,3‐dimethyl‐3a,9a‐diphenyl‐1,3a,4,9a‐tetrahydroimidazo[4,5‐e]thiazolo[2,3‐c]‐1,2,4‐triazin‐2,8(3H,7H)‐dione was observed under basic conditions. 相似文献
138.
Petrásková L Charvátová A Prikrylová V Kristová V Rauvolfová J Martínková L Jiménez-Barbero J Aboitiz N Petrus L Kren V 《Journal of chromatography. A》2006,1127(1-2):126-136
A new separation method based on the combination of exclusion and ion exchange chromatography in borate buffer was developed. It allows semi-preparatory and preparatory separation of isobaric N-acylhexosamines (C-2 epimers) and corresponding methyl glycosides (anomers and tautomers). Three types of polyolic gels were tested for these separations. Ion-exchange HPLC was used as a rapid and reliable method for the quantification of the respective analytes. NMR studies of the interactions of N-acetylhexosamines with borate confirmed the importance of a proper stereochemical arrangement of acetamido sugars for their interactions with borate anions. 相似文献
139.
Ludmila V Roze Anindya Chanda Maris Laivenieks Randolph M Beaudry Katherine A Artymovich Anna V Koptina Deena W Awad Dina Valeeva Arthur D Jones John E Linz 《BMC biochemistry》2010,11(1):33
Background
Filamentous fungi in the genus Aspergillus produce a variety of natural products, including aflatoxin, the most potent naturally occurring carcinogen known. Aflatoxin biosynthesis, one of the most highly characterized secondary metabolic pathways, offers a model system to study secondary metabolism in eukaryotes. To control or customize biosynthesis of natural products we must understand how secondary metabolism integrates into the overall cellular metabolic network. By applying a metabolomics approach we analyzed volatile compounds synthesized by Aspergillus parasiticus in an attempt to define the association of secondary metabolism with other metabolic and cellular processes. 相似文献140.
Ilona Šperlingová Ludmila Dabrowská Vladimír Stránský Šárka Dušková Jan Kučera Monika Tvrdíková Milon Tichy 《Analytical and bioanalytical chemistry》2010,397(2):433-438
Ethylene glycol monobutyl ether (EGBE), an industrial solvent, is absorbed by the body not only by inhalation but also by
dermal absorption (liquid or vapour). EGBE is metabolized to butoxyacetic acid (BAA). Pooled freeze-dried urine candidate
reference material (RM) was prepared from urine obtained from persons occupationally exposed to EGBE. This material has the
advantage of containing butoxyacetic acid in both the free and conjugated (glutamine and glycine) forms, as found in native
urine. In all GC method modifications used, acid hydrolysis was used to release BAA from its conjugated form. The amount of
butoxyacetic acid in homogeneity and stability testing was measured by GC after derivatisation with N-tert-butyldimethylsilyl-N-methyltrifluoroacetamide. Detection was by MS in EI mode, in the authors’ laboratory. For interlaboratory comparison of the
reference material GC methods with MS, FID, and ECD were used. Different extraction solvents (dichloromethane–isopropanol
2:1, ethyl acetate, or dichloromethane) and derivatisation reagents (trimethylsilyldiazomethane, N-tert-butyldimethylsilyl-N-methyltrifluoroacetamide) were used. Using ANOVA (at the statistical level α = 0.05) no changes were found in the concentration of butoxyacetic acid during fifteen month isochronous stability testing,
or in homogeneity testing. The uncertainty contributions were u
h = 8.8 mg L−1 and u
s = 6.5 mg L−1. The concentration of butoxyacetic acid in freeze-dried urine RM was evaluated from the results of eight laboratory data
sets within an interlaboratory comparison by use of the interactive statistical software IPECA. The contribution to total
uncertainty derived from interlaboratory comparison was u
i = 12.7 mg L−1. The reference value (c = 273 ± 33 mg L−1) is an unweighted arithmetic average of accepted results. The value is traceable to the pure butoxyacetic acid (98% w/w; Acros Organic #257760010) used as calibrant. The uncertainty given is combined expanded uncertainty derived from the results
from interlaboratory comparison, and from homogeneity and stability tests (k = 2). The reference material will be used to verify method performance in the biological monitoring of occupational exposure
to EGBE. 相似文献