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21.
A one-pot procedure that has been developed for the rapid and efficient synthesis of sulfonamides from sulfonic acids and amines using cyanuric chloride (2,4,6-trichloro-1, 3,5-triazine, TCT, CyCl) and N,N-dimethyl formamide at room temperature has been described.  相似文献   
22.
A novel, simple, accurate, and low-cost colorimetric device based on an Android smartphone was developed for sulfonamide determination. A software program was developed to be used for analyzing the samples. Various parameters for digital colorimetric detection were investigated and optimized, such as the volume of the sample drop, the type of sample holder, the distance from the mobile phone camera to the sample holder, and the effect of ambient light. From the optimized conditions, a calibration curve was created by the intensity of blue channel for sulfonamides for the concentration range of 0.5–2.5?µg?mL?1 with good linearity and a regression coefficient (R2) of 0.996. The results obtained by the smartphone method were compared with a spectrophotometric procedure at the 95% confidence level (n?=?3). Both methods correlated well with a regression coefficient (R2) of 0.997. The limit of detection of both methods was equal to 0.11?µg?mL?1. The developed smartphone system was successfully used for the determination of sulfonamides in pharmaceutical and veterinary formulations with recoveries of 102 and 98.7%, respectively. The developed method provides good accuracy (relative error <5%) and precision (relative standard deviation <7%) and offers simple, convenient, rapid, and inexpensive determination of sulfonamides.  相似文献   
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A simple, practical, and metal‐free protocol has been developed for the synthesis of sulfonamides from sodium sulfinates and various amines through an iodine‐mediated S N bond formation reaction at room temperature. This green reaction is cost‐effective, operationally straightforward, and especially proceeds under very mild conditions to afford the target products in good to excellent yields (up to 98%).

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25.
4-Aminoantipyrine was utilized as key intermediate for the synthesis of pyrazolone derivatives bearing biologically active moieties. The newly synthesized compounds were characterized by IR, 1H- and 13C-NMR spectral and microanalytical studies. The compounds were screened as anticancer agents against a human tumor breast cancer cell line MCF7, and the results showed that (Z)-4-((3-amino-5-imino-1-phenyl-1H-pyrazol-4(5H)-ylidene)methylamino)-1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one 5, 3-(4-bromophenyl) -1-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)-4-oxo-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carbonitrile 13, 1-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1-Hpyrazol- 4-yl)-3-(4-iodophenyl)-4-oxo-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carbonitrile 14, 3,3′-(4,4′-sulfonylbis(4,1-phenylene))bis(1-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol- 4-yl)-4-oxo-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carbonitrile) 16, (Z)-1-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)-2-hydrazono-4-oxo-3-phenyl-1,2,3,4-tetrahydropyrimidine-5-carbonitrile 17, (Z)-1-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)-4-oxo-3-phenyl-2-(2-phenylhydrazono)-1,2,3,4-tetrahydro pyrimidine-5-carbonitrile 18, and (Z)-4-(3-amino-6-hydrazono-7-phenyl-6,7-dihydro pyrazolo[3,4-d]pyrimidin-5-yl)-1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one 19 were the most active compounds with IC50 values ranging from 30.68 to 60.72 μM compared with Doxorubicin as positive control with the IC50 value 71.8 μM.  相似文献   
26.
固相萃取-高效液相色谱测定奶粉中磺胺类抗生素残留   总被引:1,自引:0,他引:1  
建立了测定奶粉中磺胺嘧啶和磺胺甲噁唑的固相萃取-高效液相色谱法。奶粉溶于水后经亚铁氰化钾和醋酸锌溶液处理后离心去除脂肪,过C18柱,用水淋洗,甲醇洗脱,洗脱液用于高效液相色谱分析。采用C18柱,流动相为甲醇∶0.08%乙酸=40∶60,检测波长272nm,流速0.8mL/min。结果表明,两种磺胺药物在0.05~1μg/mL的范围内线性良好,回收率为96.8%~97.5%。本方法具有灵敏度高,重复性好等特点。  相似文献   
27.
吴鹏  赵新淮 《食品科学》2007,28(12):382-386
目的:建立快速溶剂提取动物组织中磺胺类抗生素残留的方法,并将该方法与超声波辅助提取法、匀浆法比较。方法:以样品添加回收率为指标,探索各种提取参数的影响,优化提取条件。结果:选出了加速溶剂提取法的最适条件:二氯甲烷为提取溶剂,提取压力500psi,温度40℃,整个提取过程需时23min,提取溶剂12ml,六种磺胺的添加回收率均高于80%,相对标准偏差在9%以下。结论:加速溶剂提取与超声波辅助提取法、匀浆相比,是一种快速、高效的提取方法。  相似文献   
28.
Aberrant activation of the mitogen‐activated protein kinase (MAPK)‐mediated pathway components, RAF‐MEK‐ERK, is frequently observed in human cancers and clearly contributes to oncogenesis. As part of a project aimed at finding inhibitors of B‐Raf, a key player in the MAPK cascade, we originally identified a thiazole derivative endowed with high potency and selectivity, optimal in vitro ADME properties, and good pharmacokinetic profiles in rodents, but that suffers from elevated hERG inhibitory activity. An optimization program was thus undertaken, focused mainly on the elaboration of the R1 and R2 groups of the scaffold. This effort ultimately led to N‐(4‐{2‐(1‐cyclopropylpiperidin‐4‐yl)‐4‐[3‐(2,5‐difluorobenzenesulfonylamino)‐2‐fluorophenyl]thiazol‐5‐yl}‐pyridin‐2‐yl)acetamide ( 20 ), which maintains favorable in vitro and in vivo properties, but lacks hERG liability. Besides exhibiting potent antiproliferative activity against only cell lines bearing B‐Raf V600E or V600D mutations, compound 20 also intriguingly shows a weaker “paradoxical” activation of MEK in non‐mutant B‐Raf cells than other known B‐Raf inhibitors. It also demonstrates very good efficacy in vivo against the A375 xenograft melanoma model (tumor volume inhibition >90 % at 10 mg kg?1); it is therefore a suitable candidate for preclinical development.  相似文献   
29.
目的 建立超高效液相色谱-串联质谱法(ultra performance liquid chromatography-tandem mass spectrometry, UPLC-MS/MS)同时测定鳗鱼中13种磺胺类、15种喹诺酮类和4种四环素类兽药残留的分析方法。方法 鳗鱼试样采用乙二胺四乙酸二钠(ethylenediaminetetraacetic acid disodium salt, Na2EDTA)-Mcllvaine提取液进行提取, HLB固相萃取柱净化, Waters ACQUITY UPLC BEH C18色谱柱分离, 以0.1%甲酸乙腈和0.1%甲酸水溶液作为流动相进行梯度洗脱; 电喷雾正离子模式下, 以多反应监测(multiple reaction monitoring, MRM)方式采集数据进行定性与定量分析, 外标法定量。结果 磺胺类、喹诺酮类及四环素类药物分别在2~50、2~50、5~100 μg/kg浓度范围内线性相关性良好, 相关系数均大于0.99; 不同加标水平的平均回收率为82.6%~110.2%, 相对标准偏差(relative standard deviations, RSDs)为3.2%~13.9%, 检出限(limits of detection, LODs)和定量限(limits of quantification, LOQs)分别为0.3~2.0 μg/kg和1.0~5.0 μg/kg。结论 本方法快速简便、灵敏可靠, 适合大批量鳗鱼中同时快速对磺胺类、喹诺酮类及四环素类兽药残留进行定性和定量检测。  相似文献   
30.
A green atom‐economical method for the synthesis of biaryl sulfonamide derivatives via palladium(II)‐catalyzed C H bond activation by employing an amino acid moiety as the bidentate directing group has been developed. The protocol proceeded efficiently in water; high yields and broad substrate scope were achieved. The reaction shows good functional group compatibility and proceeds in a highly selective manner at the ortho position of arenes connected to sulfonamide sulfur atoms. This auxiliary can be easily removed either by acidic hydrolysis, or converted into primary biaryl sulfomamides with a 30 mol % amount of CuO as catalyst. Mechanistic studies show that the present bidentate directing group is essential for promoting ortho C H bond activation of arenes connected to sulfonamide sulfur atoms.

  相似文献   

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