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91.
Ma S Sun D Simmons JM Collier CD Yuan D Zhou HC 《Journal of the American Chemical Society》2008,130(3):1012-1016
A microporous metal-organic framework, PCN-14, based on an anthracene derivative, 5,5'-(9,10-anthracenediyl)di-isophthalate (H4adip), was synthesized under solvothermal reaction conditions. X-ray single crystal analysis revealed that PCN-14 consists of nanoscopic cages suitable for gas storage. N2-adsorption studies of PCN-14 at 77 K reveal a Langmuir surface area of 2176 m2/g and a pore volume of 0.87 cm3/g. Methane adsorption studies at 290 K and 35 bar show that PCN-14 exhibits an absolute methane-adsorption capacity of 230 v/v, 28% higher than the DOE target (180 v/v) for methane storage. 相似文献
92.
The direct structural modification of GDP-mannose via the bromination and Suzuki-Miyaura cross-coupling of the unprotected sugar-nucleotide, to produce 8-substituted fluorescent analogues of GDP-mannose. 相似文献
93.
An interpenetrating microporous metal-organic framework based on a mu3-oxotrinickel basic carboxylate secondary building unit has been synthesized and structurally characterized. It exhibits pronounced gas-sorption hysteresis and selective adsorption of carbon dioxide over methane. 相似文献
94.
Pornpun Rattananakin Charles U. PittmanJr. Willard E. Collier Svein Saebø 《Structural chemistry》2007,18(3):399-407
Twelve push–pull ethylene derivatives, NH2CH=CHX, NH2C≡CCH=CHX, and −OCHX=CHX (with X=BH2, C≡N, NO2, and CH2
+) have been studied by ab initio calculations. The rotational barrier around the central double bond was chosen as a probe
for push–pull effects, as push–pull effects would remove electron density from the central double bond. The amount of reduction
of double bond character will increase with the contribution of the zwitterionic resonance hybrid structure. Complete geometry
optimizations and calculations of vibrational frequencies were performed for all minima and transition state structures of
these 12 systems. The calculations were carried out with the B3LYP and MP2 methods using the 6-311+G(d,p) and the 6-311++G(d,p)
basis sets. All the systems investigated exhibited properties consistent with push–pull effects such as elongated C=C double
bonds, dipolar electronic structures, and reduced barriers to internal rotation. 相似文献
95.
Ortho‐Stabilized 18F‐Azido Click Agents and their Application in PET Imaging with Single‐Stranded DNA Aptamers 下载免费PDF全文
Lu Wang Dr. Orit Jacobson Din Avdic Dr. Benjamin H. Rotstein Dr. Ido D. Weiss Dr. Lee Collier Prof. Dr. Xiaoyuan Chen Prof. Dr. Neil Vasdev Prof. Dr. Steven H. Liang 《Angewandte Chemie (International ed. in English)》2015,54(43):12777-12781
Azido 18F‐arenes are important and versatile building blocks for the radiolabeling of biomolecules via Huisgen cycloaddition (“click chemistry”) for positron emission tomography (PET). However, routine access to such clickable agents is challenged by inefficient and/or poorly defined multistep radiochemical approaches. A high‐yielding direct radiofluorination for azido 18F‐arenes was achieved through the development of an ortho‐oxygen‐stabilized iodonium derivative (OID). This OID strategy addresses an unmet need for a reliable azido 18F‐arene clickable agent for bioconjugation reactions. A ssDNA aptamer was radiolabeled with this agent and visualized in a xenograft mouse model of human colon cancer by PET, which demonstrates that this OID approach is a convenient and highly efficient way of labeling and tracking biomolecules. 相似文献
96.
Karadas F Yavuz CT Zulfiqar S Aparicio S Stucky GD Atilhan M 《Langmuir : the ACS journal of surfaces and colloids》2011,27(17):10642-10647
Carbon dioxide (CO(2)) adsorption capacities of several hydroxy metal carbonates have been studied using the state-of-the-art Rubotherm sorption apparatus to obtain adsorption and desorption isotherms of these compounds up to 175 bar. The carbonate compounds were prepared by simply reacting a carbonate (CO(3)(2-)) solution with solutions of Zn(2+), Zn(2+)/Mg(2+), Mg(2+), Cu(2+)/Mg(2+), Cu(2+), Pb(2+), and Ni(2+) metal ions, resulting in hydroxyzincite, hydromagnesite, mcguinnessite, malachite, nullaginite, and hydrocerussite, respectively. Mineral compositions are calculated by using a combination of powder XRD, TGA, FTIR, and ICP-OES analysis. Adsorption capacities of hydroxy nickel carbonate compound observed from Rubotherm magnetic suspension sorption apparatus has shown highest performance among the other components that were investigated in this work (1.72 mmol CO(2)/g adsorbent at 175 bar and 316 K). 相似文献
97.
98.
Galen Sedo 《Journal of Molecular Spectroscopy》2010,262(2):135-138
Eight rotational transitions of the complex (CH3)3CCN-SO3 have been recorded using pulsed-nozzle Fourier transform microwave spectroscopy and a series of ab initio calculations has been performed. The complex is a symmetric top with free or nearly free internal rotation of the SO3 and (CH3)3CCN subunits. The nitrogen-sulfur bond distance is determined to be 2.394(19) Å. Calculations at the MP2/aug-cc-pVTZ level/basis, which are in excellent agreement with the experimental results, give a binding energy of 11.0 kcal/mol relative to (CH3)3CCN and SO3. Physical properties of the system, including N-S bond length, N-S-O angle, binding energy, and the degree of electron transfer (obtained from Townes and Dailey analysis of the 14N nuclear quadrupole coupling constant) are compared with those of similar complexes. The proton affinity of the base is a useful parameter for ordering complexes in the series. 相似文献
99.
100.
The structures of the charge transfer salt tetrathiofulvalenium 2,5-diethyltetracyanoquinodimethane (TTF-DETCNQ), which undergoes a metal-insulator transition at 111°K, were examined at 120° and 81°K by single crystal X-ray diffraction. The variation of the cell parameters with temperature was determined from measurements ranging from 40°K to room temperature. The properties of TTF-DETCNQ are compared to those of the parent compound TTF-TCNQ. 相似文献