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901.
Hui Tang Can-Hui Zheng Xiao-Hui Ren Jia Liu Na Liu Jia-Guo Lv Ju Zhu You-Jun Zhou 《中国化学快报》2013,24(3):219-222
A series of 1-(benzylamino)-2-(2,4-difluorophenyl)-3-(1H-1,2,4-triazol-l-yl)propan-2-ols compounds were synthesized and evaluated for their antifungal activities in vitro.The results showed that compounds 6A and 6B exhibited good antifungal activity.Compound 6A8 showed the strongest antifungal activity,which was significantly higher than that of the lead compounds and positive-control drugs Fluconazole and Itraconazole.In particular,the antifungal activity of compound 6A8 against Candida albicans and Candida krusei(MIC80 both at 0.00097μg/mL) was 515 and 64 times that of Fluconazole,respectively.The structure-activity relationships of the synthesized compounds were discussed,and the docking model of the target compounds with fungal lanosterol 14α-demethylase (CYP51) was analyzed. 相似文献
902.
The title complex l-[CuⅡ4(Hvap)2(vap)2(MeOH)2](CIO4)2 1 has been synthesized and characterized by EA. IR,TGA,solid-state CD spectra and X-ray single-crystal analyses(l-H2vap’.a Schiff base ligand derived from the condensation of o-vanillin and l-2-amino-3-phenyl-l-propanol).Complex 1 crystallizes in monoclinic system,chiral space group P21 with a =10.4257(18).b = 21.695(4),c = 15.721(3)A,β= 94.443(3).V= 3545.1(11) 3,Z=2,Cu4C70H78N4O22Cl2.Mr= 1652.42,Dc= 1.548 g/cm3, F(000)= 1704 andμ(MoKα) = 1.338 mm-1.The final R = 0.0682 and wR = 0.1420 for 6170 observed reflections with I > 2σ(I) and R = 0.1775 and wR = 0.1830 for all data.The structure of complex 1 contains a boat-shaped(Cu4O4} motif.The solid-state CD spectra confirm the chiral nature of complex 1. 相似文献
903.
以三嵌段共聚物P123(聚环氧乙烷-聚环氧丙烷-聚环氧乙烷,PEO20-PPO70-PEO20)为还原剂和保护剂,比较了水热法和溶剂热法对纯Ir和IrPd合金催化剂合成及其电催化氧化甲醇(MOR)性能的影响。对于纯Ir催化剂,在相同条件下,溶剂热法能更好地促进Ir前驱体的还原。对于IrPd合金催化剂,溶剂热法可制得表面富含Ir但MOR活性较低的核壳结构产物(IrPd-S)。水热反应得到的不同原子比(IrPd、Ir2Pd、IrPd2)的产物粒径更小,元素分布更均匀。其中比例为1∶1的IrPd (IrPd-H)催化剂的MOR电催化活性最高。上述结果表明,通过调节溶剂类型以及P123的结构诱导作用,可以有效地调节纯Ir和IrPd合金催化剂的结构、表面组成和电催化活性。 相似文献
904.
905.
茚三酮衍生高效毛细管电泳法测定纯奶中的甘氨酸含量 总被引:1,自引:0,他引:1
建立了茚三酮衍生高效毛细管电泳法测定纯奶中甘氨酸含量的方法,该法可选择性测定甘氨酸含量。使用氯化镁为蛋白沉淀剂,沉淀效果较好,研究了甘氨酸–茚三酮聚合物衍生条件,确定最佳实验条件为:未涂层弹性石英毛细管柱(60 cm×75μm,有效长度49 cm),分离缓冲溶液为3.5 mmol磷酸二氢钾–8.2 mmol磷酸氢二钠(pH 6.8),检测波长为570 nm,电泳电压为25 kV,进样压力为25 kPa,进样时间为3 s,电泳温度为室温。甘氨酸的线性范围为2.00~200.00μg/mL,检出限为0.14μg/mL,线性相关系数不小于0.999。甘氨酸的加标回收率为88.7%~107.2%,测定结果的相对标准偏差为2.9%~4.2%(n=6)。该法简便、快速、准确,可用于测定纯奶中甘氨酸含量。 相似文献
906.
The development of technologies for mass spectrometry imaging is of substantial research interest. Mass spectrometry is potentially capable of providing highly specific information about the distribution of compounds in tissues, with high sensitivity. The in-situ analysis needed for tissue imaging requires MS to be performed under conditions different from the traditional ones, typically with intensive sample preparation and optimized for pharmaceutical applications. In this paper we critically review the current status of MS imaging with different methods of sample ionization and discuss the 3D and quantitative imaging capabilities which need further development, the importance of the multi-modal imaging, and the balance between the pursuit of high-resolution imaging and the practical application of MS imaging in biomedicine. 相似文献
907.
This work concentrates on extending the utilization of multiple dual mode (MDM) counter‐current chromatography in chiral separations. Two aromatic acids, 2‐(6‐methoxy‐2‐naphthyl)propionic acid (NAP) and 2‐phenylpropionic acid (2‐PPA), were enantioseparated by MDM counter‐current chromatography using hydroxypropyl‐β‐cyclodextrin (HP‐β‐CD) as chiral selector. The two‐phase solvent systems consisting of n‐hexane/ethyl acetate 0.1 mol/L phosphate buffer pH 2.67 containing 0.1 mol/L HP‐β‐CD (7.5:2.5:10 for NAP and 7:3:10 for 2‐PPA, v/v/v) were used. Conventional MDM and modified MDM were compared according to peak resolution under current separation mechanism. The influence of elution time after the first‐phase inversion and number of cycles for MDM were investigated. Peak resolution of NAP and 2‐PPA increased from 0.62 to 1.05 and 0.72 to 0.84, respectively, using optimized MDM conditions. Being an alternative elution method for counter‐current chromatography, MDM elution greatly improved peak resolution in chiral separations. 相似文献
908.
Qiuyun Wang Yajin Xiong Baozhu Lu Jun Fan Sheng Zhang Shengrun Zheng Weiguang Zhang 《Journal of separation science》2013,36(8):1343-1348
N‐(2,4‐dinitrophenyl)‐proline and N‐(2,4‐dinitrophenyl)‐serine were enantiomerically resolved on the BSA chiral stationary phase by HPLC in reversed‐phase mode. Effects of chromatographic conditions on enantioseparation and elution order have been investigated in detail. For these two samples, reversal of enantiomer elution order was observed by changing buffer pH, the content of acetonitrile, or alcohol modifiers in mobile phase, which is firstly reported in the BSA chiral stationary phase studies. More interestingly, combined effect between buffer pH and the content of acetonitrile was also observed. In addition, coelution range of enantiomers varied along with the content of acetonitrile in mobile phase. 相似文献
909.
Advances in pesticide biosensors: current status, challenges, and future perspectives 总被引:1,自引:0,他引:1
Public concern over pesticide residues has been increasing dramatically owing to the high toxicity and bioaccumulation effects of pesticides and the serious risks that they pose to the environment and human health. It is therefore crucial to monitor pesticide residues by using various analytical methods and techniques, especially highly sensitive, highly selective, simple, rapid, cost-effective, and portable ones. Biosensor strategies have become research hotspots and ideal candidates for pesticide detection, having such features as high sensitivity, fast response, robustness, low cost and miniaturization, as well as in situ and real-time monitoring. This review covers advances in the design and fabrication of biosensors for pesticide detection since 2005. Special emphasis is placed on the state-of-art selection of receptors, the use of different transduction techniques and fast screening strategies, and the application of various biosensors developed in food and environmental safety. Both advantages and drawbacks of these techniques are then summarized. Finally, challenges, strategies, and perspectives in further developing pesticide biosensors are also discussed. Figure
Principle of operation of pesticide biosensors 相似文献
910.
The C-I bond dissociation enthalpies (BDE) of various organic iodides were calculated using high-level theoretical methods including MP2 and CCSD(T) with extrapolated basis set as well as a number of density functional theory methods. After systematic evaluation of the theoretical results against available experimental C-I BDEs, it was found that the MPW LYPIM method gave the lowest root mean square error. We, therefore, used this method to examine the substituent effects on different categories of C(sp3)-I and C(sp2)-I bonds. Fur thermore, the remote substituent effects on the C-I BDEs of substituted iodobenzenes and substituted (iodomethyl)benzenes were also investigated at the same level. The C-I BDEs of typical heteroaromatic iodides including five-membered and six-membered heterocyclic iodides were also examined. 相似文献