全文获取类型
收费全文 | 108篇 |
免费 | 6篇 |
专业分类
化学 | 82篇 |
晶体学 | 1篇 |
力学 | 3篇 |
数学 | 6篇 |
物理学 | 22篇 |
出版年
2023年 | 1篇 |
2022年 | 5篇 |
2021年 | 5篇 |
2020年 | 5篇 |
2019年 | 5篇 |
2018年 | 1篇 |
2017年 | 1篇 |
2016年 | 4篇 |
2015年 | 4篇 |
2014年 | 8篇 |
2013年 | 5篇 |
2012年 | 5篇 |
2011年 | 9篇 |
2010年 | 4篇 |
2009年 | 5篇 |
2008年 | 5篇 |
2007年 | 5篇 |
2006年 | 2篇 |
2005年 | 3篇 |
2004年 | 5篇 |
2003年 | 4篇 |
2002年 | 6篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1998年 | 1篇 |
1994年 | 1篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1989年 | 1篇 |
1986年 | 1篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1975年 | 1篇 |
1968年 | 1篇 |
1934年 | 2篇 |
排序方式: 共有114条查询结果,搜索用时 15 毫秒
51.
The impurity-induced charge density in jellium is calculated by solving the Schr?dinger equation self-consistently. The resulting
phase shifts have been used to estimate the value of residual resistivity for dilute Zr-H system, which comes out to be 0.50
μΘ cm/at.%. An alternative form of one-parameter-screened Coulomb potential, which is more suitable than the customary Thomas-Fermi
potential, is suggested. The calculated self-energy by using new potential is found close to its value obtained by Darbyet al. 相似文献
52.
53.
Garima Jindal Raghavan B. Sunoj 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(17):4521-4525
Insights into chiral induction for an asymmetric sulfoxidation reaction involving a single oxygen atom transfer are gained through analyzing the stereocontrolling transition states. The fitting of the substrate into the chiral cavity of a new class of imidodiphosphoric Brønsted acids, as well as weak C H⋅⋅⋅π and C H⋅⋅⋅O noncovalent interactions, are identified as responsible for the observed chiral induction. 相似文献
54.
J. I. S. Khattar D. P. Singh Namita Jindal N. Kaur Y. Singh P. Rahi A. Gulati 《Applied biochemistry and biotechnology》2010,162(5):1327-1338
Limnothrix redekei PUPCCC 116, a filamentous cyanobacterium, has been identified through 16S rRNA gene sequencing. Exopolysaccharides (EPS)
of this organism have been isolated and characterized chemically, and its rheological properties were compared with commercial
xanthan. The organism produced 304 μg EPS/ml culture in 21 days. The rate of EPS production was maximum (313 μg EPS/mg protein/day)
during the initial days of growth, and it decreased to 140 μg EPS/mg protein/day during 18-21 days of growth. Chemical analysis
of EPS revealed the presence of glucose/mannose, ribose, rhamnose, and uronic acid. Fourier transformed infrared spectrum
of EPS further revealed the presence of methyl and carboxyl groups besides C–N groups indicating the presence of peptidyl
moieties. Elemental analysis of EPS showed the presence of 4.97% N. The organism under continuous light produced 102% more
EPS compared to when grown under a light/dark cycle of 14/10 h. The rheological properties of EPS were comparable with commercial
xanthan gum. 相似文献
55.
Zinki Jindal N.K. Verma 《Physica E: Low-dimensional Systems and Nanostructures》2009,41(10):1752-1756
One-dimensional (1D) cadmium sulphide (CdS) nanostructures, including micro/nanorods, and nanostructures resembling flowers and cactus have been synthesized by electrochemical template deposition technique, using polycarbonate membranes, by controlling various reaction parameters. These 1D CdS nanostructures were characterized structurally through the X-ray diffraction (XRD) studies and morphologically through scanning electron microscopy (SEM). It was found that apart from the dimensions of the pores of the templates, the geometrical morphologies of the CdS 1D nanostructures were significantly influenced by the synthesizing parameters also. The optical characterization has been done by UV–visible absorption and room-temperature photoluminescence (PL) studies. 相似文献
56.
Ratnakar SJ Viswanathan S Kovacs Z Jindal AK Green KN Sherry AD 《Journal of the American Chemical Society》2012,134(13):5798-5800
PARACEST redox sensors containing the NAD(+)/NADH mimic N-methylquinolinium moiety as a redox-active functional group have been designed and synthesized. The Eu(3+) complex with two quinolinium moieties was nearly completely CEST-silent in the oxidized form but was "turned on" upon reduction with β-NADH. The CEST effect of the Eu(3+) complex containing only one quinolinium group was much less redox-responsive but showed an unexpected sensitivity to pH in the physiologically relevant pH range. 相似文献
57.
First-principles calculations based on density functional theory were performed to study the structural and electronic properties of sulphur substitution-doped boron nitride (BN) nanotubes, using the theory as implemented in SIESTA code, which uses non-conserving pseudo-potentials in fully non-local form and atomic orbitals as the basis set. The generalized gradient approximation (GGA) was used for the exchange–correlation (XC) potential. The tube selected was a (10, 0) BN nanotube that fell in the range of energy gap independent of the tube diameter. The electronic and structural properties for sulphur substitution in the boron and the nitrogen sites were studied. The structural arrangement in equilibrium conditions for S shows an outward radial deformation around the sulphur atom in the tube. The bandgap of the pristine BN nanotubes was found to be significantly modified on doping. 相似文献
58.
V. K. Jindal† V. V. Sreedhara Rao‡ 《International Journal of Mathematical Education in Science & Technology》2013,44(4):499-506
This paper describes a mathematical model capable of analysing a sugarcane sett cutting operation. Monte Carlo technique is applied for generating the hypothetical sugarcanes to be cut into setts of uniform length. The probability density functions of the variables such as the sugarcane lengths, nodal spacings and the end piece lengths for a given sugarcane variety constitute the inputs to the model. The experimental and model predicted proportions of the multibudded setts for a few arbitrarily selected cut lengths are compared and further improvements in the model are discussed. It is shown that the developed model can be effectively used to analyse the sugar cane sett cutting operation to meet the selection criteria for the multibudded setts. 相似文献
59.
Jason N. Byrd Nakul Jindal Robert W. Molt Jr. Rodney J. Bartlett Beverly A. Sanders Victor F. Lotrich 《Molecular physics》2013,111(22):3459-3470
We present second-order molecular cluster perturbation theory (MCPT(2)), a linear scaling methodology to calculate arbitrarily large systems with explicit calculation of individual wave functions in a coupled-cluster framework. This new MCPT(2) framework uses coupled-cluster perturbation theory and an expansion in terms of molecular dimer interactions to obtain molecular wave functions that are infinite order in both the electronic fluctuation operator and all possible dimer (and products of dimers) interactions. The MCPT(2) framework has been implemented in the new SIA/Aces4 parallel architecture, making use of the advanced dynamic memory control and fine-grained parallelism to perform very large explicit molecular cluster calculations. To illustrate the power of this method, we have computed energy shifts, lattice site dipole moments, and harmonic vibrational frequencies via explicit calculation of the bulk system for the polar and non-polar polymorphs of solid hydrogen fluoride. The explicit lattice size (without using any periodic boundary conditions) was expanded up to 1000 HF molecules, with 32,000 basis functions and 10,000 electrons. Our obtained HF lattice site dipole moments and harmonic vibrational frequencies agree well with the existing literature. 相似文献
60.
A series of twenty compounds inclusive of bidentate Schiff bases derived from condensation of 4‐methyl‐3‐thiosemicarbazide with substituted derivatives of napthaldehyde/benzaldehyde/salicylaldehyde and their mononuclear Co (II), Ni (II), Cu (II) and Zn (II) complexes in molar ratio (1:1) were synthesized and characterized. The coordination behavior, modes of bonding and overall geometry of the compounds was known from the elemental analysis, spectral techniques (IR, UV–Vis, 1H NMR, 13C NMR, ESR and ESI‐mass), magnetic moment measurements, molar conductance, thermal and powder XRD studies. The studies revealed octahedral geometry for all the complexes where ligands coordinated in a neutral bidentate manner (NS) via nitrogen atom of azomethine group and sulphur atom of thione group with the metal centre. In vitro biological effects of the compounds were tested against four bacterial species and two fungal strains. The results indicated that the metal complexes showed a marked enhancement in biocidal activity in comparable with the parent Schiff bases. In vitro anticancer activity against the malignant tumor cell lines; human alveolar adenocarcinoma epithelial cell line (A549), human breast adenocarcinoma cell line (MCF7), human prostate cancer cell line (DU145) and human normal lung cell line (MRC‐5) using MTT assay, exposed compound 16 as a leading member with lowest IC50 value of 10.6 ± 0.14 μM against (A549) cell line. 相似文献