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71.
含质子柠檬酸氧钒(V)配合物中间体的合成和晶体结构 总被引:1,自引:0,他引:1
合成了含质子柠檬酸氧钒(V)配合物中间体NaK3[VO2(Hcit)]2·7H2O,用红外光谱和X射线衍射进行了结构表征。结果表明:晶体属单斜晶系,P21/n空间群。晶胞参数a=1.1258(2)nm,b=1.5774(3)nm,c=16559(1)nm,β=98.568(9)°,V=2.908(1)nm^3,Z=4,Dc=1.851g·cm^-3,F(000)=1640,μ(Cu Kα)=104 相似文献
72.
Brucella was an intracellular parasite, which could infect special livestock and humans. After infected by Brucella, livestock’s reproductive system could be affected and destroyed resulting in huge economic losses. More seriously, it could be contagious from livestock to humans. So far, there is no available vaccine which is safe enough for humans. On this point, subunit vaccine has become the new breakthrough of conquering brucellosis. In this study, Brucella rL7/L12-BLS fusion protein was used as an antigen to immunize rabbits to detect the immunogenicity. The results of antibody level testing assay of rabbit antiserum indicated rL7/L12-BLS fusion protein could elicit rabbits to produce high-level IgG. And gamma interferon (IFN-γ) concentrations in rabbit antiserum were obviously up-regulated in both the rL7/L12 group and rL7/L12-BLS group. Besides, the results of quantitative real-time PCR (qRT-PCR) showed the IFN-γ gene’s expression levels of both the rL7/L12 group and rL7/L12-BLS group were obviously up-regulated. All these results suggested Brucella L7/L12 protein was an ideal subunit vaccine candidate and possessed good immunogenicity. And Brucella lumazine synthase (BLS) molecule was a favorable transport vector for antigenic protein. 相似文献
73.
The problem of quadratic prediction for population quadratic quantities in finite populations has been considered in the literature. In this paper, we mainly aim at extending the ordinary quadratic prediction problems to a general case, and derive the representations of the two essentially unique optimal predictors: one is an optimal invariant quadratic unbiased predictor, and the other is an optimal invariant quadratic (potentially) biased predictor. Further, we show that the two predictors are nonnegative and reasonable by considering an extreme situation, and apply resulting conclusions to a special model with a compound symmetric variance matrix. In addition, we propose a notion of quadratic sufficiency with regard to the optimal prediction problems by employing materials derived in the first part, and investigate corresponding characterizations in detail. 相似文献
74.
将6-溴-2,2'∶6',2"-三联吡啶转化为6-甲酰基-2,2'∶6',2"-三联吡啶, 再将其与表面组装有氨基硅氧烷的石英片基反应, 使甲酰基与片基表面的氨基反应生成Schiff碱型化合物, 在氨基化片基表面成功地固定6-甲酰基-2,2'∶6',2"-三联吡啶及相应的钌配合物, 并用紫外-可见吸收光谱及光电子能谱(XPS)检测联吡啶及相应钌配合物的组装过程. 相似文献
75.
The structural stability of cyclophilin A (CypA) was investigated using H/D exchange and temperature coefficients of chemical shifts of amide protons, monitored by 213 heteronuclear NMR spectroscopy. Amide proton exchange rates were measured by H/D exchange experiments for slow-exchange protons and measured by SEA (Solvent Exposed Amides)-HSQC experiments for fast-exchange protons. Temperature coefficients of chemical shifts and hydrogen exchange rates of amide protons show reasonably good correlation with the protein structure. Totally, 44 out of 153 non-proline assigned residues still exist in 86 d of hydrogen-deuterium exchange at 4 ℃, suggesting that CypA structure should be highly stable. Residues in secondary structures of α2, β1, β2, β5, β6 and β7 might constitute the hydrophobic core of the protein. The change in free energy of unfolding ( △Gu^H2O ) of CypA was estimated to be (21.99± 1.53) kJ·mol^-1 by circular dichroism (CD). The large free energy change is also an indicator of the high structural stability. 相似文献
76.
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78.
山西省商品房市场的发展规律 总被引:4,自引:0,他引:4
本文通过对山西省 1998年至 2002年共 50个月份的月度商品房销售面积 (使用商品房销售面积克服了价格波动的影响 )的实证分析,建立了一个结合普通线性模型 (OLS)、非参数核估计(KernelEstimation)、以及时间序列分析(TimeSeries)的统计预测模型。此模型既能够很好地分离出商品房销售面积随时间的增长趋势,又能够很好地刻画它在各个年度周期内部光滑的季节规律。基于此模型,山西省每年商品房销售面积的规律被刻画为四个周期,即:增长期、衰退期、调整期、以及结束期。从中不难看出商品房销售规律的个性。在分析各地区商品房市场规律时,不能照搬全国商品房市场的相关规律,更不能照搬国外的测算结果。 相似文献
79.
A convenient method for the chemoselective protections of both aliphatic and aromatic aldehydes has been developed. Ruthenium(III) trichloride (0.1 mol %) has found to be an highly efficient catalyst in the acetalizations of aldehydes with various simple alcohols such as methanol, ethanol, or diols such as 1,2-ethylanediol and 1,3-propanediol under mild reaction conditions. 相似文献
80.