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1.
探索了机械搅拌、配料组成、晶化参数等因素对SAPO-34和SAPO-5磷铝分子筛水热合成的影响,考察了混粒(颗粒混合)工艺和研粉(粉体研磨)工艺对“磷铝分子筛/尖晶石”复合催化剂制备的影响。与SAPO-34分子筛相比,SAPO-5分子筛晶体对机械作用的耐受性较强。用XRD、N2物理吸附、FESEM、EDS研究了材料的结构和织构特征。对比了四种复合催化剂的CO催化加氢性能。能够使复合催化剂更能抑制C–C偶合、从而更富产低碳烃的物相次序为:SAPO-34 > SAPO-5 > “ZnAlCrO4”尖晶石相。能够使复合催化剂具有更高CO加氢活性(即CO转化率)的物相次序为:“ZnAlCrO4”尖晶石相 > SAPO-34 > SAPO-5。  相似文献
2.
Xue Fu Zhu Yu Decoction, a famous formula that has been used for treating many blood stasis‐caused diseases for many centuries, comprises 11 kinds of traditional Chinese medicines. A convenient, efficient, and rapid analytical method was developed to simultaneously determine the major compounds in this decoction. An ultra‐high performance liquid chromatography with hybrid ion trap time‐of‐flight mass spectrometry method was used to rapidly separate and detect the major constituents of the decoction. Using this technique, we identified or tentatively identified 34 compounds, including 21 flavonoids, 5 terpenoids, 3 organic acids, 2 lactones, 1 alkaloid, 1 amino acid, and 1 cyanogenic glycoside. The MS analysis of these constituents was described in detail. Findings may contribute to future metabolic and pharmacokinetic studies of this medicine.  相似文献
3.
A rapid and sensitive liquid chromatography with high‐resolution mass spectrometry method with multiple data processing algorithms was developed and applied for the metabolite profiling of evodiamine and its analogous alkaloids in rat plasma after the administration of Wu‐Zhu‐Yu decoction. All samples were purified using hydrophilic‐lipophilic balanced solid‐phase extraction cartridges and analyzed by a Sciex TripleTOF 5600+ mass spectrometer with a 35 min liquid chromatography gradient elution. High‐resolution full‐scan mass spectrometry and information‐dependent acquisition tandem mass spectrometry data were analyzed using multiple data processing approaches. The results indicated that the detected eight prototype alkaloids could be metabolized to 58 metabolites through both phase I and phase II reactions. Oxidation was demonstrated to be the principle metabolic pathway of the parent compounds. The study contributes to the understanding of the absorption and metabolism of the alkaloids in Wu‐Zhu‐Yu decoction and provides a detailed analysis of scientific data.  相似文献
4.
A novel, sensitive and reliable ultra fast liquid chromatography‐tandem mass spectrometry (UFLC‐MS/MS) method has been developed and validated for simultaneous quantitation of eight main active ingredients (evodiamine, rutaecarpine, dehydroevodiamine, limonin, ginsenoside Rb1, Rd, Re and Rg1) in rat plasma after oral administration of Wu‐Zhu‐Yu (WZY) decoction, which is a celebrated and widely used Traditional Chinese Medicine formula for the treatment of headache. The analytes and internal standard (IS) were separated on a SHIM‐PACK XR‐ODS II column, and the detection was performed on a UFLC‐MS/MS system with turbo ion spray source. The lower limits of quantification were 1.5, 0.5, 1.0, 2.0, 2.0, 1.0, 0.5 and 0.2 ng ml−1 for evodiamine, rutaecarpine, dehydroevodiamine, limonin, gensenoside Rb1, Rd, Re and Rg1, respectively. Linearity, accuracy, precision and absolute recoveries of the eight analytes were all within satisfaction. The IS‐normalized matrix factor was adopted for assessing the matrix effect and accompanied with a satisfactory result. The validated method has been successfully applied to compare pharmacokinetic profiles of the eight active ingredients in rat plasma between normal and headache rats after administration. Exact pharmaceutical effect of WZY decoction on headache was demonstrated by the ethological response of headache rats induced by nitric oxide donor after administration. The results indicated that the absorption of evodiamine, rutaecarpine, gensenoside Rb1, Re and Rg1 in headache group were significantly higher than those in normal group with similar concentration–time curves while no significant differences existed in limonin and ginsenoside Rd between the two groups. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献
5.
本文扼要叙述了汪猷先生的学术渊源、他一生的主要科学活动与成就、在这些科学活动与成就中所表现出来的学术思想以及他的学术思想在中科院上海有机所的传承与发扬。  相似文献
6.
渠瑾 《大学化学》2017,32(9):85-92
记述了我国著名有机合成化学家、兰州大学资深教授李裕林先生在祖国的大西北近半个世纪的学术生涯中的主要贡献,其中包括三尖杉酯碱类化合物的半合成,以及生物标志化合物、狼毒素、大环二萜类、桉烷类和沉香呋喃类天然产物的全合成研究。  相似文献
7.
《Analytical letters》2012,45(11):1929-1936
Abstract

A highly sensitive spectrophotometric method for determination of palladium by the new chromogenic reagent (BPT) has been developed. In the presence of cetyltrimethylammonium bromide(CTMAB), palladium reacts with BPT to form a stable yellow complex in HAc-NaAc buffer solution of pH 4.6-5.6 at 294.4 nm with a molar absorptivity of 2.46 x 105 l mol−1 cm−1. The method is simple, rapid and sensitive. Trace amounts of palladium in mineral and catalyst samples have been satisfactorily determined by the method.  相似文献
8.
In this paper, HPLC-ESI-MS technique was used to analyze the hypocholesterolemic extracts of 'Xue-Fu-Zhu-Yu decoction', a traditional Chinese medicine consisting of six crude drugs (i.e. Paeonia lactiflora, Ligusticum chuanxiong, Citrus aurantium, Carthamus tinctorius, Prunus persica and Bupleurum falcatum). A total of 17 compounds were identified and their plant derivations were also distinguished. Nine compounds among them were unambiguously determined as oxypaeoniflorin, amygdalin, albiflorin, paeoniflorin, ferulic acid, naringin, hesperidin, senkyunolide I and neohesperidin by comparing the retention times (tR), UV spectra and m/z values with those of the reference compounds. The other eight compounds were tentatively identified as prunasin, 6-hydroxy-kaempferol 3,6-diglucoside, 6-hydroxykaempferol 3-rutinoside-6-glucoside, galloylpaeoniflorin, 6-hydroxy-kaempferol 3-glucoside, anhydrosafflor yellow B, narirutin and kaempferol 3-rutinoside by MS2 spectra and the comparison of their UV spectra and MS spectra with literature data.  相似文献
9.
在水热的条件下合成了多钒硼酸盐(enH2)4Na4H3[(VO)12O6B18O42]8H2O, 化学式为C8H59B18N8Na4O68V12 (Mr=2253.45), 用单晶X射线衍射方法测定了它的结构, 该晶体属单斜晶系, P21/n空间群, 晶胞参数为a = 13.8989(4), b = 16.1954(5), c = 14.4520(4) ?β = 94.7490(5), V= 3241.95(16) ?, Z = 2, Dc = 2.308 g/cm3, ?= 1.819mm-1, F(000) = 2234, 4798个可观察衍射点(I > 2s(I)), 最终结构精修到偏离因子R = 0.0449, wR = 0.1163, S = 0.996。在该化合物的结构中, V12B18簇是由环状的B18O42通过18个B(μ3-O)V键被2个V6O18环夹在中间组成的, V12B18簇通过4个Na+与相邻的簇相连, 形成二维网状结构, 孔道尺寸为6.109×10.562 拧?  相似文献
10.
采用电絮凝法处理脱硫废水中重金属离子,研究去除过程的影响因素及动力学模型,并对电絮凝产物进行分析。考察电絮凝时间、电流密度、废水pH、曝气量对电絮凝法处理重金属离子效果的影响。结果表明,电絮凝时间40min,电流密度4mA/cm2,废水pH=7,曝气量0.4m3/h时,四种金属去除率达90%。电絮凝产物为铁的多核羟基络合物,且去除过程具有一级动力学反应特征。  相似文献
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