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121.
The adsorption of NO and its reaction with H2 over polycrystalline Pd were investigated using flash desorption technique and ultraviolet photoelectron spectroscopy under 10?5 Pa pressure range of reactants and surface temperatures between 300 and 900 K. NO was adsorbed dissociatively onto the Pd surface above 500 K, and the heat of dissociative adsorption was ca. 126 kJ/mol. Atomic nitrogen was observed to accumulate on the Pd surface during the NO-H2 reaction, whose desorption rate exhibited second order kinetics and is expressed as follows: Vd = 10?9.8 ± 0.3exp(?67(kJ/mol)/RT) (cm2/atom·s). Hydrogenation of the adsorbed nitrogen proceeded rapidly at 485 K. It was confirmed from these results that formation of N2 and NH3 in the NO-H2 reaction proceeds through this atomically adsorbed nitrogen. Pd-N bond energy and enthalpies of some intermediate states of the NO-H2 reaction were estimated. 相似文献
122.
A chirality-memorizing saddle-shaped porphyrin (12H) with 3,5-dipyridylphenyl side arms at the opposite meso positions underwent supramolecular polymerization in CH2Cl2 with a chiral Pd(II) complex of 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl (PdII(BINAP)), forming a ladder-shaped polymer (32H) with a prevailing one-handed helical chirality. When this polymer was poured into AcOH containing 1,3-bis(diphenylphosphino)propane (DPPP) as a decomplexing agent, 32H was depolymerized in a stereochemically retentive way to give optically active 12H, hydrogen-bonded with AcOH. Although a cyclodimeric reference of 32H, formed from 22H having two 3-pyridylphenyl meso substituents in conjunction with PdII(BINAP), behaved similar to 32H, the translation efficiency of helical chirality was lower than that in the case with 32H. 相似文献
123.
Koseki T Onishi H Takahashi Y Uchida M Machida Y 《Chemical & pharmaceutical bulletin》2008,56(10):1384-1388
It was attempted to produce novel furosemide (FS) fast-disintegrating tablets by direct compression. The combination of FS, microcrystalline cellulose, croscarmellose sodium and xylitol was used as the basic formulation, and sucrose stearic acid ester (SSE) was chosen as an additional additive. The tablets with SSE were prepared by the simple addition of SSE, using a lyophilized mixture of FS and SSE or using a FS/SSE mixture obtained by evaporation of their ethanol solution. Only the tablets, produced using the FS/SSE mixture obtained by organic solvent (ethanol) evaporation, showed hardness of more than 30 N and a disintegration time of less than 20 s, which were the properties suitable for fast-disintegrating tablets. These properties were considered to result from well-mixed and fine-powdered SSE and FS. 相似文献
124.
Dr. Yu Cao Dr. David T. Rodgers Dr. Juanjuan Du Insha Ahmad Eric N. Hampton Dr. Jennifer S. Y. Ma Dr. Magdalena Mazagova Dr. Sei‐hyun Choi Dr. Hwa Young Yun Dr. Han Xiao Dr. Pengyu Yang Xiaozhou Luo Dr. Reyna K. V. Lim Holly M. Pugh Dr. Feng Wang Dr. Stephanie A. Kazane Dr. Timothy M. Wright Dr. Chan Hyuk Kim Prof. Peter G. Schultz Dr. Travis S. Young 《Angewandte Chemie (International ed. in English)》2016,55(26):7520-7524
Chimeric antigen receptor T (CAR‐T) cells have demonstrated promising results against hematological malignancies, but have encountered significant challenges in translation to solid tumors. To overcome these hurdles, we have developed a switchable CAR‐T cell platform in which the activity of the engineered cell is controlled by dosage of an antibody‐based switch. Herein, we apply this approach to Her2‐expressing breast cancers by engineering switch molecules through site‐specific incorporation of FITC or grafting of a peptide neo‐epitope (PNE) into the anti‐Her2 antibody trastuzumab (clone 4D5). We demonstrate that both switch formats can be readily optimized to redirect CAR‐T cells (specific for the corresponding FITC or PNE) to Her2‐expressing tumor cells, and afford dose‐titratable activation of CAR‐T cells ex vivo and complete clearance of the tumor in rodent xenograft models. This strategy may facilitate the application of immunotherapy to solid tumors by affording comparable efficacy with improved safety owing to switch‐based control of the CAR‐T response. 相似文献
125.
Takeda C Takahashi Y Seto I Kawano G Takayama K Onishi H Machida Y 《Chemical & pharmaceutical bulletin》2007,55(8):1164-1168
For the treatment of chronic inflammation in the oral cavity, we attempted to develop bioadhesive tablets of bovine lactoferrin (B-LF). Pectin was used as a bioadhesive polymer, and the influence of the degree of esterification and the molecular weight of pectins on the characteristics of B-LF tablets were investigated. Concerning bioadhesive force, a tendency increasing the value according to increase of the esterification of the pectin was confirmed. Sustained release of B-LF from the tablets was observed as the esterification increased, and a possibility for prediction of the time required to release 50% of B-LF by using the equation given by the degree of esterification and the logarithm of the molecular weight was suggested. Pectin cross-linked with Ca(2+) (Ca-PC) was also used for the preparation of the B-LF tablets. Prolonged release of B-LF from the tablets was observed as the Ca(2+) in Ca-PC increased. Our findings suggest that pectin with a high degree of esterification is suitable as a bioadhesive polymer since high bioadhesive force and sustained release are shown. Furthermore, a possibility that the B-LF release could be controlled by adjusting the Ca(2+) concentration in Ca-PC was suggested. 相似文献
126.
[structure: see text]. The self-assembly in aqueous solution of tripyrazolate trianion linkers (H3L = 1 and 2) with coordinated dimetallic clips leads to the formation of Pd12L4 cages with interior cavities of 1800 Angstroms3 and 1500 Angstroms3, respectively, confirmed by 1H NMR, 13C NMR, cold spray ionization mass spectrometry (CSI-MS), and single-crystal X-ray analysis. 相似文献
127.
[structure: see text] Treatment of a chiral sulfonamide with Et(2)Zn gave quantitatively its Zn complex and then the structure was determined by X-ray crystallographic analysis. Reaction of prochiral N-Boc-2-amino-2-alkyl-1,3-propanediols with Ac(2)O in the presence of 5 mol % of chiral sulfonamide-Zn complex catalyst afforded the corresponding chiral monoacetyl products in 70-92% yields with 70-88% ee values. The proposed mechanism for the catalytic monoacetylation of a prochiral 1,3-propanediol was presented on the basis of CSI-MS analysis. 相似文献
128.
Water-Nafion phase equilibria and proton conductivities were measured in two ways. First, Nafion was in contact with saturated water vapor. Second, Nafion was in contact with liquid water at the same temperature. At 29 degrees C, for preboiled, vapor-equilibrated Nafion exposed to water with an activity = 1 and air pressures ranging from 0 to 0.96 bar, the water content was lambda = 23 +/- 1 mol H(2)O/mol SO3-. For the preboiled, liquid-equilibrated membrane, lambda = 24 +/- 2. At 100% relative humidity (RH), the water content of preboiled Nafion decreased as the temperature rose from 30 to 80 degrees C but did not recover its initial water content when the temperature returned to 30 degrees C. The water content of predried Nafion at 1 atm and 30 degrees C was lambda = 13.7 +/- 0.2 when vapor-equilibrated and lambda = 13.1 +/- 0.5 when liquid-equilibrated. A Nafion membrane originally boiled in water had much higher liquid- and 100% RH vapor-equilibrated proton conductivities than the same membrane originally dried at 110 degrees C with a RH less than 2%. The liquid-equilibrated and 100% RH vapor-equilibrated membrane conductivities were the same when the membrane had the same thermal history. The conductivity data was fit to a model, and the water content was determined at different temperatures. The predried membrane water content increased with temperature, and the preboiled membrane's water content changed slightly with temperature. Both water sorption and proton-conductivity data do not exhibit Schroeder's paradox. These studies and previous results suggest that Schroeder's paradox is resolved when attention is given to the thermal history of the absorbing polymer. 相似文献
129.
Ryo Onishi Keigo Matsuda Keiko Takahashi Ryoichi Kurose Satoru Komori 《International Journal of Multiphase Flow》2011
This study presents an attempt to retrieve collision kernel values from changes in the droplet size distribution due to collision growth. Original linear and nonlinear inversion schemes are presented, which use the simple a priori assumption that the total collision rate is given by the sum of the gravitational and turbulent contributions. Our schemes directly handle binned (discretized) size distributions and, therefore, do not require any assumptions on distribution functional forms, such as the self-similarity assumption. To validate the schemes, three-dimensional direct numerical simulation (DNS) of colliding droplets in steady isotropic turbulence is performed. In the DNS, air turbulence is calculated using a pseudo-spectral method, while droplet motions are tracked by the Lagrangian method. Comparison between the retrieved collision kernels and the collision kernels obtained directly from the DNS show that for low Reynolds number flows both the linear and nonlinear inversion schemes give good accuracy. However, for higher Reynolds number flows the linear inversion scheme gives significantly larger retrieval errors, while the errors for the nonlinear scheme remain small. 相似文献
130.
Hye Y. Ji Sei‐Ryang Oh Hyeong‐Kyu Lee Dong H. Na Hye S. Lee 《Journal of separation science》2011,34(15):1828-1833
Styraxlignolide A is a pharmacologically active ingredient isolated from Styrax japonica Sieb. et Zucc. A rapid, selective, and sensitive liquid chromatographic method with electrospray ionization tandem mass spectrometry was developed for use in the quantification of styraxlignolide A in rat plasma. Styraxlignolide A was extracted from rat plasma using ethyl acetate at neutral pH. The analytes were separated on an Atlantis dC18 column using a mixture of methanol and ammonium formate (10 mM, pH 3.0) (70:30, v/v) and detected by tandem mass spectrometry in multiple reaction monitoring mode. The standard curve was linear (r2=0.9978) over the concentration range of 100?10000 ng/mL. The lower limit of quantification was 100 ng/mL using 50 μL of plasma sample. The coefficient of variation and relative error for intra‐ and inter‐assays at four QC levels were 1.6–8.3% and from ?12.0 to ?1.7%, respectively. The present method was applied successfully to the pharmacokinetic study of styraxlignolide A after intravenous administration of styraxlignolide A at a dose of 10 mg/kg in male Sprague–Dawley rats. 相似文献