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61.
A novel and rapid microwave extraction and ultra high performance liquid chromatography with tandem mass spectrometry method was developed and validated for the simultaneous determination of 25 bioactive constituents (including two new constituents) in Fructus Alpinia oxyphylla. The optimized conditions of the microwave extraction was a microwave power of 300 W, extraction temperature of 80°C, solvent‐to‐solid ratio of 30 mL/g and extraction time of 8 min. Separation was achieved on a Waters ACQUITY UPLC® HSS C18 column (2.1 mm× 50 mm, 1.8 μm) using gradient elution with a mobile phase consisting of acetonitrile and 1 mM ammonium acetate at a flow rate of 0.2 mL/min. This is the first report of the simultaneous determination of 25 bioactive constituents in Fructus Alpinia oxyphylla by ultra high performance liquid chromatography with tandem mass spectrometry. The method was validated with good linearity, acceptable precision and accuracy. The validated method was successfully applied to determine the contents of 25 bioactive constituents in Fructus Alpinia oxyphylla from different sources and the analysis results were classified by hierarchical cluster analysis, which indicated the effect of different cultivation regions on the contents of constituents. This study provides powerful and practical guidance in the quality control of Alpinia oxyphylla and lays the foundation for further research of Alpinia oxyphylla.  相似文献   
62.
A high-performance capillary electrophoresis with electrochemical detection (CE-ED) method has been developed for the determination of phytoestrogens from the pericarps and seeds of Sophora japonica L. in this work. Genistin, genistein, rutin, kaempferol and quercetin are important bioactive constituents in these plants. The effects of several factors such as the acidity and concentration of running buffer, the separation voltage, the applied potential and the injection time on the CE-ED procedure were investigated. Under the optimum conditions, the five analytes could be well separated within 18 min in a 75 cm length capillary (i.d. 25 microm) at the separation voltage of 16 kV in a 50 mmol L(-1) borax running buffer (pH 9.0). A 300 microm diameter carbon disk electrode was used as the working electrode positioned carefully opposite the outlet of the capillary in a wall-jet configuration at the potential of +950 mV (vs SCE). Detection limits (S/N = 3) ranged from 1.1 x 10(-7) to 2.8 x 10(-7) g mL(-1) for all fi ve analytes. This method was successfully used to analyse dried Flos sophorae immaturus, pericarps and seeds of dried Fructus sophorae after a relatively simple extraction procedure, and the assay results were satisfactory.  相似文献   
63.
《Electrophoresis》2018,39(7):1006-1013
In this study, a capillary zone electrophoresis (CZE) method was first developed to identify three microconstituents of isomeric pentacyclic triterpene acids (PTAs including oleanolic acid (OA), ursolic acid (UA) and betulinic acid (BA)) in Forsythiae Fructus (FF). The baseline separation of PTAs by CZE were eventually achieved in a background electrolyte (BGE) containing 50.0 mmol/L borax and 0.5 mmol/L β‐cyclodextrin (β‐CD) at pH 9.5 within 13.0 min. Herein, it was not only the compositions of BGE were detail investigated for rapid and good separation, but also the binding ratio and the equilibrium constants (K) for OA, UA and BA with β‐CD was estimated by double reciprocal equation to well understand the separation mechanism. The proposed method allowed the LODs of PTAs were averaged at 1.50 μg/mL with UV detection (at 200 nm). The interday RSD of migration time and peak area were around 2.0 and 4.7% (n = 5), respectively. Thus, the content of PTAs in 19 FF real samples distinguished from maturation stages and geographical areas in China was quantified with the proposed method. Depending on the amount of each PTA in FF, it was demonstrated these microconstituents might benefit to identify their harvested time even qualities.  相似文献   
64.
张弦飞  杨军丽  陈娟  师彦平 《色谱》2018,36(5):417-424
枸杞作为传统的中药材,具有滋补肝肾、益精明目的功效,亦可作为功能性食品被广泛食用。基于超高效合相色谱-质谱(UPC~2-MS),建立了一种快速、灵敏地定量测定枸杞中甜菜碱(指标化合物)含量的新方法。采用ACQUITY UPC2BEH 2-EP色谱柱(150 mm×2.1 mm,1.7μm),以0.7 mL/min超临界CO_2-甲醇(80∶20,v/v)等度洗脱,成功分离了枸杞中的甜菜碱。在该分离过程中,0.1%(v/v)甲酸作为改性剂;背压为1.31×10~7Pa;柱温为40℃;进样体积为1μL;保留时间为3 min。质谱检测工作于电喷雾(ESI)正离子模式和选择离子监测(SIR)模式。在上述条件下得到线性回归方程。其相关系数为0.999 2,检测范围为0.5~50.0μg/mL,检出限为0.013μg/mL。随后,通过对精度、重复性、稳定性和加标回收率(平均值96.3%)的分析,验证了该方法的有效性。最后,将所建立的方法应用于11批样品的分析。结果表明,该方法可较好地用于枸杞的质量控制与分析评价。  相似文献   
65.
Precise identification and differentiation among those congeneric Traditional Chinese Medicines (TCMs) or derived from the same plant trend to be more challenging, particularly in the absence of appearance characteristics. Three TCMs, involving Gleditsiae Sinensis Fructus (GSF), Gleditsiae Fructus Abnormalis (GFA), and Gleditsiae Spina (GS), recorded in Chinese Pharmacopoeia (2020 edition) are derived from Gleditsia sinensis, but prescribed for different clinical uses. The documents aimed to compare their chemical differences are rare, to date. An untargeted metabolomics approach, based on ultra-high performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UHPLC/QTOF-MS), was elaborated to unveil the potential chemical markers to differentiate among GSF, GFA, and GS. Good chromatographic separation of all the GSF/GFA/GS components was achieved within 33 min by utilizing a BEH C18 column, while data-independent MSE in the positive mode was selected for profiling the metabolic features. Notably, the high-mass saponins (1300–2500 Da) gave unique protonated precursors ([M + H]+) in the positive ESI mode, compared with those complicated ion species occurring in the negative mode. Pattern recognition chemometrics analysis of 45 batches of G. sinensis samples could unveil 70 significantly altered ions assigned as 46 potentially differential components. The positive/negative high-accuracy MS2 data analysis, phytochemical isolation/NMR analysis, and searching of an in-house library of G. sinensis, were utilized for structural elucidation. Three compounds (saikachinoside A, locustoside A, and locustoside B) rich in GSF could be the markers to differentiate from GFA/GS, while four components were characteristic for GS. These results obtained can greatly benefit the quality control of TCMs derived from G. sinensis.  相似文献   
66.
Ding L  Luo XB  Tang F  Yuan JB  Guo M  Yao SZ 《Talanta》2008,74(5):1344-1349
Dehydroandrographolide, andrographolide and geniposide are the main active constituents of many herbal medicines, e.g., Fructus gardeniae, Common Andrographis Herb. They are used as the markers to control the quality of such herbal medicines and their herbal preparations. In this paper, a simple and sensitive high-performance liquid chromatographic (HPLC) method coupled with photodiode array detection (DAD) and electrospray mass spectrometry (ESI/MS) were developed to determine the three compounds simultaneously in extracts of medicinal herbs and herbal preparations produced by different companies. The extracts were separated on a C18 reversed phase HPLC column, with a gradient solvent system, the time for the separation of the three target analytes was 10 min. The abundance ions were recorded using selected ion monitoring (SIM) mode with m/z 297.3, 297.3 and 411.1 for dehydroandrographolide, andrographolide and geniposide, respectively. The limit of detection for dehydroandrographolide, andrographolide and geniposide were 20, 30 and 150 ng mL−1, respectively. The proposed method was successfully applied to the determination of the contents of the compounds in related to medicinal herbs and preparations.  相似文献   
67.
吴娜  沈谦  蔡光明  赵艳玲  何群  王峰 《化学学报》2009,67(7):700-704
将巴马火麻仁木脂素酰胺类的粗提物采用硅胶柱层析法以V(氯仿)∶V(甲醇)=85∶15洗脱分离, 分离产物经快原子轰击质谱(FAB-MS)、核磁共振(NMR)鉴定为大麻酰胺A (cannabisin A). 以1,1-二苯基-2-苦基肼自由基(DPPH•)、超氧阴离子自由基 、羟自由基(OH•)三种不同自由基体系研究火麻仁木脂素酰胺类的粗提物、大孔树脂纯化后的精提物及cannabisin A的活性清除作用. 结果表明在一定的剂量范围内, 三者均有显著的活性清除作用, 且与剂量呈明显量效关系. 精提物的清除作用最强, 尤其是在OH•体系中, 其清除活性为粗提物的13倍.  相似文献   
68.
69.
超临界CO_2萃取连翘挥发油的正交试验和GC-MS分析   总被引:17,自引:0,他引:17  
采用正交试验法对超临界CO2萃取连翘挥发油的条件进行了研究;结果显示最佳萃取条件为萃取压力30MPa,萃取温度35℃,解析压力6.7MPa,解析温度50℃,粉碎度0.55mm;按对结果的影响大小依次排列为萃取温度,粉碎度,萃取压力,解析压力,解析温度;用气相色谱-质谱联用技术测定了最佳萃取条件所得连翘挥发油的化学成分,从中鉴定出21种成分,并测定了其相对含量,主要成分为α-蒎烯、β-蒎烯、萜品醇-4、α-萜品醇、苯甲醇等。  相似文献   
70.
非水反相高效液相色谱法分离测定枸杞子中的类胡萝卜素   总被引:12,自引:0,他引:12  
李忠  彭光华  张声华 《色谱》1998,16(4):341-343
采用非水反相高效液相色谱法在ODS柱上比较了不同流动相系统对枸杞子中类胡萝卜素的分离效果,探索了枸杞子中类胡萝卜素的最佳分离条件。  相似文献   
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