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排序方式: 共有3236条查询结果,搜索用时 31 毫秒
931.
932.
Saeed‐ur‐Rehman Muhammad Arshad Masood Ahmad Khalid Masud Abdul Ghani Nasima Arshad Ammad Hussain Qureshi Sohail Akhtar Ghauri 《中国化学会会志》2000,47(3):501-508
Some of the bis‐complexes of a derivative of phenhomazine (dibenzo[b,f][1:5]diazocine‐6:12‐dione; PHZD) with Ni(II), Cu(II), Co(II), Cd(II), Zn(II) and Hg(II) of the general formula M(PHZD)2X2 [where X = C1, Br and I], were prepared and identified. These complexes have been characterised on the basis of elemental analysis, and spectroscopic, magnetic and conductance data. The thermal mode of decomposition and thermal stability of these complexes was investigated on the basis of the respective thermal curves in a static air atmosphere. The thermoanalytical investigations indicate that these complexes undergo two‐step changes as temperature is raised, except for Cd(II) and Hg(II) complexes, with the formation of metal oxides as end product. The degradation mechanism of the complexes has also been proposed. 相似文献
933.
Bilal Akram Dr. Wenxiong Shi Hao Zhang Shaheed Ullah Muhammad Khurram Prof. Dr. Xun Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(22):8575-8579
A single-step solution-based strategy is used to obtain 2D Janus-like free-standing ultrathin nanosheets build from two structurally unrelated species, that is, polyoxomolybdate (POM) and CoO. A controlled 2D-to-1D morphological transition was achieved by judiciously adjusting the solvent choice. These POM-CoO heterostructures can behave as an ideal catalyst for the epoxidation of styrene. Benefiting from their amphiphilic nature, these 2D POM-CoO nanosheets have also been used as surfactant to emulsify immiscible solvents. It is anticipated that structurally diverse polyoxometalates will offer promise as design elements for variety of structurally and compositionally tunable van der Waals integrated heteromaterials having a broad range applications. 相似文献
934.
Muhammad Aizaz Ud Din Syed Irfan Sami Ullah Dar Syed Rizwan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(25):5662-5666
The design of a three-dimensional structure for an Ir-based catalyst offers a great opportunity to improve the electrocatalytic performance and maximize the use of the precious metal. Herein, a novel wet chemical strategy is reported for the synthesis of an IrRuMn catalyst with a sphere structure and porous features. In the synthetic process, the combined use of citric acid and formamide is requisite for the formation of the sphere structure. This method leads to a favorable 3D IrRuMn sphere structure with many fully exposed active sites. Furthermore, an alloying noble metal, such as Ir or Ru, with the transition metal leads to enhanced oxygen evolution reaction (OER) activity. The doping of a transition metal, such as Mn, is an interesting example, because it exhibits stability and activity in both acidic and alkaline media. For the OER, the IrRuMn sphere catalyst exhibits an overpotential of 260 mV at a current density of 10 mA cm−2 in strongly acidic 0.1 m HClO4, which is superior to that of a commercial IrO2/C catalyst. This approach provides a novel way to synthesize an Ir-based multimetallic spherical electrocatalyst, which exhibits exceptional efficiency for the acidic OER. It will pave the way for new approaches to the practical utilization of PEM electrolyzers. 相似文献
935.
NiS (nickel sulfide)–In2O3 (indium oxide) nanostructures and NiS–In2O3 decorated on graphene oxide (GO) were demonstrated by ultrasonic/hydrothermal method. The structural study demonstrates the preparation of bixbyite and hexagonal phase of In2O3 and NiS for all of the synthesized catalysts. The band gap of the synthesized catalyst was determined to be in the range of 2.30–3.00 eV. A morphological evaluation by field emission scanning electron microscopy of NiS–In2O3 decorated on graphene oxide shows support for the NiS–In2O3 on the graphene oxide layer. Different test parameters were performed to study the phase and morphology. The particle sizes of the In2O3, NiS–In2O3 and NiS–In2O3/GO nanocomposites were 56.0, 62.0 and 66.0 nm, respectively. The photocatalytic performance of NiS–In2O3/GO nanocomposites was examined for the degradation of methylene blue dye under a UV lamp. The prepared sample shows 98.25% photocatalytic degradation within 40 min and at pH 9. With the presence the NiS and GO, the photo-degradation capacities of In2O3 and NiS–In2O3 are improved owing to the low band gap being calculated in UV–vis DRS analysis. The high ratio of NiS causes the highest photocatalytic properties of NiS–In2O3 nanocomposites owing to the enhancement of charge separation efficiency and generation of hydroxyl radicals. This study presents a facile and low-cost method to prepare highly active NiS–In2O3/GO nanocomposites. The antibacterial data indicate the significant properties of NiS–In2O3/GO nanocomposites for this study. 相似文献
936.
Khan Muhammad A. Mahmood Hasan Khan Mumtaz S. Iqbal Tariq Ahmad Pervaiz Shafique Muhammad Naeem Muhammad 《Journal of Solid State Electrochemistry》2020,24(5):1123-1132
Journal of Solid State Electrochemistry - In this research work, CuO nanostructures were synthesized using atmospheric pressure microplasma (AMP) electrochemical process. The synthesized CuO... 相似文献
937.
Bo Chen Bo Zhang JiHai Yu FuCong Fei Muhammad Naveed Yi Zhang Zhe Sun XianGang Wan FengQi Song 《中国科学:物理学 力学 天文学(英文版)》2020,(2):111-116
Performing angle-resolved photoemission spectroscopy(ARPES) and theoretical calculations for ZrSnTe, we find a nodal line in the kx-ky plane with a tiny gap and two nodal lines without gaps along the kzdirection. The constant energy contours are plotted in the kx-ky plane at a photon energy of 30 e V to examine the gapping feature of the nodal line. In addition, we depict the band dispersions along the Γ-M and Γ-X directions from the ARPES images at photon energies ranging from 24 to 40 e V. The kz mapping confirms the presence of stable Dirac points with obvious kzdependences along the M-A and X-R directions. In this paper, we report the two types of nodal lines associated with the theoretical local-density approximation calculations, broadening the horizons of nodal-line semimetal research. 相似文献
938.
Mokashi Imran Khan Sher Afghan Abdullah Nur Azam Bin Azami Muhammad Hanafi Afzal Asif 《Journal of Thermal Analysis and Calorimetry》2020,141(6):2555-2571
Journal of Thermal Analysis and Calorimetry - The use of Li-ion battery in electric vehicles is becoming extensive in the modern-day world owing to their high energy density and longer life. But... 相似文献
939.
对HL-2A 偏滤器靶板和固定孔栏位置的石墨瓦进行了离线激光诱导击穿光谱(LIBS)测量,比较分析了沉积行为,初步得到了不同位置沉积层粒子种类(Fe、Si、H、D 等元素)及其深度的变化。与飞行时间二次离子质谱仪(TOF-SIMS)所得结果进行了对比,发现离子深度变化形貌趋同。根据沉积层有效信号激光数,得到激光烧蚀速率约为270nm/脉冲。 相似文献
940.
Muhammad Haji Hanif Muddasir Tahiri Iftikhar Ahmad Versiani Muhammad Ali Shah Faheem Khaliq Obaid Ali Syed Tahir Ahmed Safeer 《Research on Chemical Intermediates》2018,44(10):6387-6400
Research on Chemical Intermediates - Among the reactive oxygen species, the superoxide anion radical (O 2 ·? ) has a fundamental role in several biological functions. Consequently, its... 相似文献