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161.
基于超高效液相色谱-四极杆-飞行时间质谱(UPLC-QTOF-MS),使用UNIFI软件建立91种农药残留的筛查与确证方法,进行定性方法验证并应用于流通市场中茶叶的筛查检测。通过对收集的农药认证标准物质(CRM)分析,构建91种农药化合物的质谱数据库。样品经乙腈提取,固相萃取柱净化,Acquity BEH C18色谱柱分离,在MSE模式下进行全信息采集(ESI+), UNIFI软件对数据进行匹配分析。设置保留时间最大偏差为±0.1 min,精确质量偏差阈值为±5×10-6,可识别加合物形式包括[M+H]+、[M+Na]+、[M+K]+、[M+NH4]+。参照SANTE/11813/2017指南进行定性方法学验证。在21份茶叶样品中添加混合标准溶液至4个水平(0.01、0.05、0.10、0.20 mg/kg),确定每种农药在茶叶样品中的筛查检出限(SDL),共评估了1 911种农药/样品组合。发现有66种农药的SDL为0.01 mg/... 相似文献
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XIONG Zi-jun DU Peng LI Bian XU Li-li ZHEN Xue-chu FU Wei .Key Laboratory of Smart Drug Delivery Ministry of Education & PLA 《高等学校化学研究》2011,(4):655-660
The serotonin 2A(5-HT2A) receptor has been implicated in several neurological conditions and potent 5-HT2A antagonists have therapeutic effects in the treatment of schizo phrenia and depression.In this study,a potent novel 5-HT2A inhibitor 05245768 with a Ki value of (593.89±34.10) nmol/L was discovered by integrating a set of computational approaches and experiments(protein structure prediction,pharmacophore-based virtual screening,automated molecular docking and pharmacological bioassay).The 5-HT2A recept... 相似文献
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Yi‐Hong Tang Guang‐Xin Xia Zhao‐Lin Sun Zhi‐Xiong Li Cheng‐Gang Huang 《Biomedical chromatography : BMC》2010,24(11):1147-1151
To profile the anti‐Coxsackie virus B3 constituents of Radix Astragali, an HPLC‐DAD‐MSn analytical method, combined with an in vivo test, has been developed to identify the constituents of the active part, which has been demonstrated to have potency to inhibit the proliferation of virus in cardiac muscle, alleviate infraction in heart and elevate the survival rate of the animal. By comparing their retention time and MS data with those obtained from the authentic compounds and the published data, a total of 19 compounds, including 11 isoflavonoids and eight saponins, were identified, among which one pterocarpane glucoside was reported for the first time. The present study provides an approach to rapidly screening bioactive constituents in traditional Chinese medicines. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
168.
LIU Jing-Jing 《中国物理C(英文版)》2010,34(11)
According to a new electron screening theory,we discuss the beta decay rates of nuclide 56Fe,56Co,56Ni,56Mn,56Cr and 56V with and without strong electron screening (SES).The results show that SES has only a slight effect on the beta decay rates for ρ/μe 108 g/cm3.However the beta decay rates would be influenced greatly for ρ/μe 108 g/cm3.Due to SES,the maximum values of the C-factor (in %) on beta decay rates of 56Fe,56Co,56Ni,56Mn,56Cr and 56V is of the order of 95.03%,35.02%,98.05%,80.33%,98.30% and 98.71% at T9 = 4.0 and 98.83%,98.89%,99.65%,10.32%,4.10% and 40.21% at T9 = 7.0,respectively. 相似文献
169.
Pekka Tiikkainen Antti Poso Olli Kallioniemi 《Journal of computer-aided molecular design》2009,23(4):227-239
In this work, we calculated the pair wise chemical similarity for a subset of small molecules screened against the NCI60 cancer
cell line panel. Four different compound similarity calculation methods were used: Brutus, GRIND, Daylight and UNITY. The
chemical similarity scores of each method were related to the biological similarity data set. The same was done also for combinations
of methods. In the end, we had an estimate of biological similarity for a given chemical similarity score or combinations
thereof. The data from above was used to identify chemical similarity ranges where combining two or more methods (data fusion)
led to synergy. The results were also applied in ligand-based virtual screening using the DUD data set. In respect to their
ability to enrich biologically similar compound pairs, the ranking of the four methods in descending performance is UNITY,
Daylight, Brutus and GRIND. Combining methods resulted always in positive synergy within a restricted range of chemical similarity
scores. We observed no negative synergy. We also noted that combining three or four methods had only limited added advantage
compared to combining just two. In the virtual screening, using the estimated biological similarity for ranking compounds
produced more consistent results than using the methods in isolation. 相似文献
170.
Ale Ricka Libor Dostl Roman Jambor Vladimír Buchta Jirí Brus Ivana Císarov Michal Holcapek Jaroslav Holecek 《应用有机金属化学》2002,16(6):315-322
A set of seven [2,6‐bis(dimethylaminomethyl)phenyl]diphenyltin(IV) ({[(CH3)2NCH2]2(C6H3)}(C6H5)2Sn+X?) ionic organotin(IV) compounds (X = Br, NO3, CN, SCN, SeCN, BF4 and PF6) has been prepared and characterized by electrospray ionization mass spectrometry, 1H NMR spectroscopy in CDCl3,119Sn NMR in CDCl3 and DMSO‐d6 solution, as well as by 13C and 119Sn CP/MAS NMR spectroscopy and X‐ray diffraction techniques in the solid state. The in vitro antifungal activity of these water‐soluble ionic organotin(IV) compounds was compared with starting compounds and the antifungal drugs currently in clinical use. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献