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101.
以3,3-二甲基-1-(1H-1,2,4-三唑基)-2-丁酮肟为原料,经醚化、肼解及腙化3步反应得到(E)-N'-(取代苯亚甲基)-2-[(Z)-3,3-二甲基-1-(1H-1,2,4-三唑-1-基)丁基-2-亚甲氨氧基]乙酰肼(3a~3u),化合物3与二乙酸碘苯(IBD)反应,合成了21个(Z)-3,3-二甲基-1-(1H-1,2,4-三唑-1-基)-2-丁酮肟-(5-芳基-1,3,4-噁二唑-2-基)甲基醚(4a~4u),化合物4的化学结构经核磁共振谱、高分辨质谱和元素分析确证.采用单晶X射线衍射仪测定了化合物4c的晶体结构.抑菌活性测试结果表明,在500 mg/L浓度下,化合物4k,4f,4j和4n对纹枯病菌的防效率分别为70.9%,60.2%,60.0%和60.6%;在25 mg/L浓度下,化合物4b,4c,4d和4e对菌核病菌的抑制率为71.8%~76.9%. 相似文献
102.
103.
Dong-Yan Hu Meng-Shun Li Wen-Wu Zhong Jian-Xin Ji Jin Zhu Wei Wei Qiang Zhang Ming Cheng 《中国化学快报》2016,27(11):1691-1695
A simple and highly efficient one-pot method for the construction of α-hydroxyketone phosphates from terminal alkynes and H-phosphine oxides has been developed in the presence of PhI(OAc)_2 and H_2O.The present protocol provides an attractive approach to α-hydroxyketone phosphates in good to high yields,with the advantages of operation simplicity,the use of commercially available materials,broad substrate scope,high atom efficiency and good tolerance to scale-up synthesis. 相似文献
104.
Hiromichi Fujioka Hideyuki KomatsuAkihito Miyoshi Kenichi MuraiYasuyuki Kita 《Tetrahedron letters》2011,52(9):973-975
Oxidative cleavage of cyclobutanols using PIDA, which leads to efficient entry of γ-hydroxy ketones, is described. When using 2-substituted cyclobutanols, γ-substituted γ-hydroxy ketones are obtained through regioselective C-C bond cleavage. 相似文献
105.
In this present work the combination of iodobenzenediacetate (PIDA)/iodine has been established as a promising reagent to promote the construction of 2-substituted benzimidazoles from 2-aminobenzylamine and a variety of easily available aldehydes/arylamines through a ring distortion strategy. The present protocol offers mild, metal free, robust conditions to synthesize 2-substituted benzimidazoles in good to excellent yields. In addition, the oxidation prone functional groups show tolerance during the reaction and after completion of the reaction pure products can be easily obtained applying hassle free filtration of the reaction mixture through silica gel bed. 相似文献
106.
Universal method for the determination of nonionic surfactant content in the presence of protein 下载免费PDF全文
Ziping Wei Susanna Bilbulian Jingning Li Ratnesh Pandey Ellen O'Connor Jose Casas‐Finet Patricia W. Cash 《Journal of separation science》2015,38(8):1318-1325
A new analytical method has been developed for the quantitative determination of ethylene glycol‐containing nonionic surfactants, such as polyethylene glycol 8000, polysorbate 80, and Pluronic F‐68. These surfactants are commonly used in pharmaceutical protein preparations, thus, testing in the presence of protein is required. This method is based on the capillary gas chromatographic analysis of ethylene glycol diacetate formed by hydrolysis and acetylation of surfactants that contain ethylene glycol. Protein samples containing free surfactants were hydrolyzed and acetylated with acetic anhydride in the presence of p‐toluene sulfonic acid. Acetylated ethylene glycol was extracted with dichloromethane and analyzed by gas chromatography using a flame ionization detector. The amount of nonionic surfactant in the sample was determined by comparing the released ethylene glycol diacetate signal to that measured from calibration standards. The limits of quantitation of the method were 5.0 μg/mL for polyethylene glycol 8000 and Pluronic F‐68, and 50 μg/mL for polysorbate 80. This method can be applied to determine the polyethylene glycol content in PEGylated proteins or the final concentration of polysorbate 80 in a protein drug in a quality control environment. 相似文献
107.
高效液相色谱法同时测定食品中丙酸钙(钠)和双乙酸钠 总被引:1,自引:0,他引:1
建立高效液相色谱法同时测定食品中的丙酸钙(钠)和双乙酸钠。采用Acclaim120 C_(18)色谱柱(150mm×4.6 mm,5μm),以1.5 g/L磷酸氢二铵溶液(用1 mol/L磷酸溶液调pH至2.7~3.5)–甲醇混合液(体积比为95∶5)作为流动相,流量为1.0 mL/min,在214 nm波长下检测。丙酸与双乙酸钠的质量浓度在0.05~0.5 mg/mL范围内线性关系良好,相关系数均大于0.999。丙酸和双乙酸钠的加标回收率分别为95.58%~98.95%,96.12%~99.25%,测定结果的相对标准偏差分别为1.50%,1.41%(n=6)。该法适用于糕点及调味品中丙酸钙(钠)和双乙酸钠含量的检测。 相似文献
108.
Weiwei Qin Shuji Yasuike Naoki Kakusawa Masatoshi Kawahata Jyoji Kurita 《Journal of organometallic chemistry》2008,693(1):109-116
The reaction of triarylantimony diacetates (6) with organoboron reagents (9) in the presence of Pd(PPh3)4 led to the formation of cross-coupling products, biaryls (10, 12 and 14-17), in moderate to excellent yields under mild conditions without any base. Similar reaction of 6 with triarylbismuthanes (18) also gave the corresponding cross-coupling products. Single crystal X-ray analysis of tri(p-tolyl)antimony diacetate (6b) and tris(p-trifluoromethylphenyl)antimony diacetate (6e) revealed the geometry of both central antimony atoms being intermediate between trigonal bipyramidal and pentagonal bipyramidal arrangement with intramolecular coordination between the antimony and two carbonyl oxygen atoms with cis orientation. 相似文献
109.
A novel palladium-catalyzed three-component carbonylative coupling reaction by use of triarylantimony diacetate, arylboronic acid and carbon monoxide (1 atm) could be attained under mild reaction conditions without any base as an additive. The reaction can be applied to a wide range of triarylantimony diacetates and boronic acids to afford the corresponding unsymmetrical biaryl ketones in good yields. 相似文献
110.