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排序方式: 共有393条查询结果,搜索用时 312 毫秒
61.
Bala Reddy Bheemareddy Mallikarjuna Pulipeta Pradeep Iyer 《Journal of carbohydrate chemistry》2019,38(1):1-19
The degree of monoclonal antibody galactosylation is known to affect complement-dependent cytotoxicity (CDC) activity by affecting C1q binding, suggesting that galactose is associated with CDC bioactivity. However, whether this association also exists under temperature stress conditions is not known. This study highlights the impact of variations in the terminal galactose content of an anti-CD20 monoclonal antibody on CDC bioactivity under high-temperature stress conditions compared with storage conditions at 2–8?°C. Drug product samples with a total galactose content of >38% showed stable CDC bioactivity at higher temperatures (45?°C), while those with 16% galactose content showed reduced CDC activity. 相似文献
62.
We generalize a recently developed method for accelerated Monte Carlo calculation of path integrals to the physically relevant case of generic many-body systems. This is done by developing an analytic procedure for constructing a hierarchy of effective actions leading to improvements in convergence of N-fold discretized many-body path integral expressions from 1/N to 1/Np for generic p. In this Letter we present explicit solutions within this hierarchy up to level p=5. Using this we calculate the low lying energy levels of a two particle model with quartic interactions for several values of coupling and demonstrate agreement with analytical results governing the increase in efficiency of the new method. The applicability of the developed scheme is further extended to the calculation of energy expectation values through the construction of associated energy estimators exhibiting the same speedup in convergence. 相似文献
63.
Veenu Bala Yashpal S. Chhonker Richard L. Sleightholm Ayrianne J. Crawford Michael A. Hollingsworth Daryl J. Murry 《Biomedical chromatography : BMC》2020,34(8):e4859
A rapid, selective, and sensitive liquid chromatography coupled with tandem mass spectrometry (MS/MS) method was developed and validated for the quantitation of the novel CDK5 inhibitor ‘20–223' in mouse plasma. Separation of analytes was achieved by a reverse-phase ACE Excel C18 column (1.7 μm, 100 × 2.1 mm) with gradient elution using 0.1% formic acid (FA) in methanol and 0.1% FA as the mobile phase. Analytes were monitored by MS/MS with an electrospray ionization source in the positive multiple reaction monitoring mode. The MS/MS response was linear over the concentration range 0.2–500 ng/mL for 20–223. The within- and between-batch precision were within the acceptable limits as per Food and Drug Administration guidelines. The validated method was successfully applied to plasma protein binding and in vitro metabolism studies. Compound 20–223 was highly bound to mouse plasma proteins (>98% bound). Utilizing mouse S9 fractions, in vitro intrinsic clearance (CLint) was 24.68 ± 0.99 μL/min/mg protein. A total of 12 phase I and II metabolites were identified with hydroxylation found to be the major metabolic pathway. The validate method required a low sample volume, was linear from 0.2 to 500 ng/mL, and had acceptable accuracy and precision. 相似文献
64.
Bala Ritu Das Debabrata Karanveer Naskar Nabanita Lahiri Susanta 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(6):2561-2572
Journal of Radioanalytical and Nuclear Chemistry - Natural radionuclide levels are studied in alluvial sediments upto the depth of 900 cm. Eighteen profiles are selected from agricultural... 相似文献
65.
Surbhi Grewal Pravesh Kumar Dr. Saonli Roy Dr. Indu Bala Dr. Chitranjan Sah Dr. Santanu Kumar Pal Dr. Sugumar Venkataramani 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(19):e202104602
Two tripodal C3-symmetric photoswitchable molecular systems T1 and T2 are reported that have extended conjugation at external and internal positions using an acryl group. The influence of the extended π-bonds in their absorption properties, thermal relaxation of the photoisomers and their propensities in forming supramolecular self-assemblies have been explored through spectroscopy, and microscopic studies. In particular, the investigations on the self-assembly have been carried out using scanning electron microscopy (SEM), transmission electron microscopy (TEM), polarized optical microscopy (POM), X-ray diffraction studies (XRD) and atomic force microscopy (AFM). Remarkably, the position of the acryl group influences the behaviour of the two target molecules in supramolecular assembly, and also in the formation of photoresponsive organic hydrogels or microcrystals. 相似文献
66.
Sharoni Gupta Chetna Ameta Pinki Bala Punjabi 《Journal of heterocyclic chemistry》2020,57(6):2410-2427
In the present paper, a novel and benign protocol for microwave enhanced one pot syntheses of 2,3-dihydro-1,5 benzodiazepine derivatives from substituted acetophenones, aryl-aldehydes and o-phenylene diamine using heterogeneous calcium ferrite/graphene oxide (CF/GO) nanocomposite has been reported. The catalyst was prepared by ultrasonication method and characterized by spectral and analytical techniques. The CF/GO nanocomposite was employed for environmentally benign synthesis of 2,3-dihydro-1,5 benzodiazepines. The synthesized benzodiazepine derivatives were screened for their antimicrobial activities against various bacteria and fungi. The present synthetic strategy offered several advantages such as excellent yields in short span of time, simple modus operandi, ease of isolation and purification of products, simple recovery and reusability of the catalyst. A tentative mechanism for synthesis of 2,3-dihydro-1,5 benzodiazepine using CF/GO nanocatalyst has also been proposed. 相似文献
67.
Raj?Pal?SharmaEmail author Rajni?Sharma Ritu?Bala Paloth?Venugopalan 《Journal of chemical crystallography》2005,35(8):595-601
The title compound was synthesized by mixing the separately dissolved trans-dichlorobis(ethylenediamine)cobalt(III) chloride and sodium 4-aminobenzoate in aqueous medium in 1:3 molar ratio and recrystallizing the product obtained, from hot water. Elemental analyses and spectroscopic techniques (IR, UV/visible, 1H and 13C NMR) were used for characterizing the complex salt. X-ray structure determination revealed an ionic structure consisting of [Co(en)2(C7H6NO2)2]+ cation, (C7H6NO2)− anion and four lattice water molecules. The complex salt crystallizes in the triclinic space group P
with cell dimensions a = 9.985(1) Å, b = 11.522(1) Å, c = 14.233(1) Å, α = 80.20(1)∘, β = 72.80(1)∘, γ = 86.43(1)∘, Z = 2, V = 1541.3(2) Å3, R1 = 0.0291, and wR2 = 0.0751. 相似文献
68.
Indu Bala 《Liquid crystals》2016,43(7):963-971
A facile synthesis of a novel covalently linked disc–rod mesogen is reported consisting of a truxene-based core attached to which are six 4-cyanobiphenyl units via flexible alkyl spacers. The compound formed a stable Langmuir monolayer at the air–water interface. The atomic force microscope study on the Langmuir–Blodgett film of the molecule reveals a tilted orientation at air–solid interfaces. 相似文献
69.
Using a one-pot synthetic approach, a single isomer of bis(diethylenetriamine)cobalt(III) cation, [Co(dien)2]3+ is obtained in bulk from the isomeric mixture (s-fac : u-fac : mer is 7 : 28 : 65) using sodium salts of benzoates (BBz-bromobenzoate, DNBz-dinitrobenzoate, MBz-methylbenzoate) in aqueous medium. Herein, we report the syntheses and characterization of three complexes of composition mer-[Co(dien)2]Cl(p-BBz)2·H2O (1), s-fac-[Co(dien)2](o,p-DNBz)3·H2O (2) and mer-[Co(dien)2]Cl(p-MBz)2·4H2O (3) in the continuation of our earlier work, where benzoate (Bz), p-chlorobenzoate (CBz), p-nitrobenzoate (NBz) and p-aminobenzoate (ABz) were used. The isomeric identification of complex cation was initially made on the basis of spectroscopic characterization (UV–visible, IR and NMR). The binding properties of [Co(dien)2]3+ with benzoates (p-BBz, o,p-DNBz, p-MBz, Bz, CBz, NBz or ABz) have been studied using standard UV–visible spectroscopic titrations in aqueous medium and comparison indicate ion association constants of s-fac > mer. The single-crystal X-ray diffraction structure analysis of 3 reveals the presence of discrete ions ([Co(dien)2]3+, chloride, p-MBz) along with four lattice water molecules. The structure of 3, with formula [Co(dien)2](p-MBz)2Cl·4H2O, consists of alternating layers made of benzoate ions and layers made of [Co(dien)2]3+, chloride and water molecules. These layers result in the formation of their respective columns and intermolecular cohesion of p-MBz within the columns of [Co(dien)2]3+ is achieved via electrostatic and H-bonding interactions. 相似文献
70.