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151.
Panax vietnamensis, or Vietnamese ginseng (VG), an endemic Panax species in Vietnam, possesses a unique saponin profile and interesting biological activities. This plant is presently in danger of extinction due to over-exploitation, resulting in many preservation efforts towards the geographical acclimatization of VG. Yet, no information on the saponin content of the acclimatized VG, an important quality indicator, is available. Here, we analyzed the saponin content in the underground parts of two- to five-year-old VG plants acclimatized to Lam Dong province. Nine characteristic saponins, including notoginsenoside-R1, ginsenoside-Rg1, -Rb1, -Rd, majonoside-R1, -R2 vina-ginsenoside-R2, -R11, and pseudoginsenoside-RT4, were simultaneously determined by HPLC coupled with UV and with a charged aerosol detector (CAD). Analyzing the results illustrated that the detection of characteristic ocotillol-type saponins in VG by CAD presented a superior capacity compared with that of UV, thus implying a preferential choice of CAD for the analysis of VG. The quantitative results indicating the saponin content in the underground parts of VG showed an increasing tendency from two to five years old, with the root and the rhizome exhibiting different saponin accumulation patterns. This is the first study that reveals the preliminary success of VG acclimatization and thereby encourages the continuing efforts to develop this valuable saponin-rich plant.  相似文献   
152.
A water-soluble pectin SB1-1 was isolated and purified from the root of Panax ginseng C. A. Mey. The HPLC analysis indicates that SB1-1 is homogenous. Its molecular weight was estimated via gel filtration to be 10000. The GC analysis indicated that it contains the monosaccharides of GalA, Gal, Ara and Rha. Their molar ratio is 2.10 : 1.00 : 0.12 : 0.13. Partial hydrolysis with acid, pectinase treatment, periodate oxidation, Smith degradation, methylation analyses, GC/MS analyses and NMR analyses were used for the structure analyses of SB1-1. The results reveal that SB1-1 has a lower branched structure. The main chain is composed of GalA and Gal; the inner part is a-1,4-linked-GalA; the border is 1,4-linked-Gal. Some of the 1,4-linked-GalA and 1.4-linked-Gal residues are substituted at O6. On an average, there is one branch for every ten hexose residues. The side chain is composed of 1,6-linked-Gal and 1,3,6-linked-Gal. The nonreduced end is composed of Rha, Ara and Gal. The main glycosidic link of SB1-1 has an a configuration.  相似文献   
153.
中药产地及生长环境的改变会对其次生代谢产物、质量产生整体性影响。近年来,三七产地从道地产地文山扩展到周边县市。为保证三七质量,中国药典以三种皂苷含量为指标对三七进行质量控制,指标较为单一,难以对三七质量进行整体性评价。通过紫外-可见分光光度法测定三七总黄酮含量,傅里叶变换红外光谱结合化学计量学建立三七总黄酮含量快速预测模型;为三七快速及整体性质量控制提供研究基础。采集云南省12个产地96个三七样品的紫外与红外光谱。记录样品紫外光谱268nm处吸光度,结合芦丁标准品线性方程计算样品中总黄酮含量。预处理红外光谱数据采用一阶(1D)、二阶导数(2D)结合SavitskyGolay平滑(7点、9点和11点)处理,Kennard-stone算法将96个个体分为2/3训练集与1/3预测集。训练集数据用于正交信号校正偏最小二乘回归(OSC-PLSR)模型的建立,1/7交叉验证用于筛选最佳主成分数,预测集数据对OSC-PLSR模型预测能力进行验证。结果显示:(1)标准品芦丁在268nm处吸光度与浓度相关系数r=0.999 7,线性浓度范围为5.6~72.0μg·mL~(-1),线性关系良好;(2)道地产区文山州3个产地以及曲靖市罗平、昆明市石林等产地三七总黄酮含量较高,平均含量高于7mg·g-1;(3)相同点数SavitskyGolay平滑之后,二阶导数模型预测能力优于一阶导数,不同处理模型预测能力具有较大差别;(4)预测模型中,2D+SG 7+OSC-PLSR(R2pre=0.976 1,RMSEP=0.325 2)与2D+SG 11+OSC-PLSR(R2pre=0.946 9,RMSEP=0.382 0)模型预测效果较好,RMSEP均小于0.4,预测值与检测值接近。傅里叶变换红外光谱结合OSC-PLSR能够对12个产地三七中总黄酮含量进行快速准确的预测,为三七整体性质量控制提供一种快速、简便、有效的检测方法。  相似文献   
154.
珠子参化学成分分析   总被引:6,自引:0,他引:6  
从珠子参根茎中分离得到7个化合物. 利用核磁共振、 质谱和红外等手段, 并结合其理化性质, 鉴定了其结构, 它们分别是24(R)-珠子参苷R1, 6-O-[β-D-吡喃葡萄糖基(1→2)-β-D-吡喃葡萄糖基]-20-O-[β-D-吡喃葡萄糖基(1→4)-β-D-吡喃葡萄糖基]-20(S)-原人参三醇、 6″-乙酰基-人参皂苷Rd、 人参皂苷Rf、 竹节参皂苷Ⅳa、 人参皂苷Rd和竹节参皂苷Ⅴ. 其中, 24(R)-珠子参苷R1和6-O-[β-D-吡喃葡萄糖基(1→2)-β-D-吡喃葡萄糖基]-20-O-[β-D-吡喃葡萄糖基(1→4)-β-D-吡喃葡萄糖基]-20(S)-原人参三醇为2个新化合物, 6″-乙酰基-人参皂苷Rd 和人参皂苷Rf为首次从珠子参根茎中得到.  相似文献   
155.
本文用常规一维1H、13C核磁共振波谱和远程异核化学位移相关谱。异核化学位移相关谱和同核化学位移相关谱技术研究了西洋参叶中首次分离出的一种Ocotillol型皂甙,确认了化学结构,并对其13C、1H NMR谱线进行了归属。  相似文献   
156.
Summary Octadecyl-porous glass was prepared and used as the packing for reversed-phase high-performance liquid chromatography. A mixture of ginsenosides, saponins of ginseng was analyzed with detection at 203 nm. Ginsenosides Rf, Rg2, Rb1, Rc, Rb2, and Rd were separated with acetonitrile-water (27.5:72.5) as the mobile phase. A well-resoluted chromatogram of ginsenosides Ro, Rg1 and Re was also obtained with acetonitrile-water (16.5:83.5). The whole separation was achieved in 12 min with a flowrate of 1 ml/min. Calibration curves of ginsenosides Rb1, Rc, Rb2, Rd, Rg1 and Re were linear up to 5 μg. It can be concluded that the rapid and accurate analysis of ginsenosides is possible by the described method.  相似文献   
157.
利用Davankov后交联反应,合成了一类兼具高比表面积和高功能基含量的季铵基(—N+(CH)3)吸附树脂,考察了树脂比表面积和功能基含量的调控规律,并将其用于三七叶总皂甙的进一步纯化.结果表明,当树脂比表面积为692m2/g,交换量为2.1mmol/g时,树脂具有最佳的纯化效果,只通过吸附—解吸一步工艺,产品纯度即可从32.0%提高到90%以上,皂甙的回收率高于95%.最后,初步探讨了树脂对皂甙和色素的吸附机理,认为树脂对皂甙的吸附是单纯的疏水性作用力,而对色素的吸附应为疏水-离子交换双重作用的协同效应.  相似文献   
158.
对中药进行快速质量控制,从整体层面反映中药的安全性与有效性具有重要意义。通过硫酸-苯酚显色反应测定三七总多糖含量,傅里叶变换红外光谱(FTIR)结合支持向量机回归(SVR)建立三七总多糖含量预测模型,以期为三七提供快速准确的质控方法。采集云南省12个产地60个三七样品的红外光谱,紫外分光光度法(UV-Vis)检测样品中总多糖含量。红外光谱经过二阶导数(2D)、正交信号校正(OSC)、小波变换(WT)和变量投影重要性(VIP)筛选等数据优化处理。SPXY算法将所有样本按2∶1的比例划分为训练集与预测集。训练集数据用于建立SVR预测模型,网格式搜索、遗传算法(GA)和粒子群优化算法(PSO)对SVR预测模型进行参数优化,预测集进一步对SVR模型的预测能力进行验证。结果显示:(1)葡萄糖标准品与三七总多糖在490 nm处存在最大共有吸收峰,490 nm可作为三七总多糖检测的定量波长;(2)文山丘北、曲靖师宗及红河蒙自等产地的三七总多糖含量较高,平均含量在25 mg·g-1以上;(3)分析3种参数优化模型的校正均方根误差(RMSEE)与预测均方根误差(RMSEP),与PSO优化模型相比,网格式搜索优化模型欠学习,GA优化模型过学习;(4)PSO-SVR模型对预测集数据预测效果最好,RMSEP=3.120 6,R2pre=83.13%,预测值与紫外检测值接近。表明FTIR结合PSO-SVR模型能够对三七中总多糖含量进行快速准确的预测,为保证三七稳定、安全与有效用药提供数据。  相似文献   
159.
The commercial products of Panax ginseng have increasing market demand and high prices due to the pharmacological activities. To obtain high profits, P. ginseng may be adulterated with lower priced morphologically similar species such as Platycodon grandiflorum, Codonopsis lanceolata, and Pueraria lobata. This study was designed to validate accurate methods for the analysis of adulteration in P. ginseng products. High-performance liquid chromatography (HPLC) and ultraperformance liquid chromatography–diode array detector–electrospray ionization–ion trap–time of flight–mass spectrometry (UPLC–DAD–ESI-IT-TOF-MS) were validated to analyze the raw plant materials, self-prepared formulations, and commercial products of P. ginseng, C. lanceolata, P. grandiflorum, and P. lobata. The developed analytical methods were confirmed by quality assurance parameters such as linearity, sensitivity, precision, and accuracy. Lobetyolin and ononin were identified as marker compounds by HPLC and confirmed by accurate mass measurement with ESI-IT-TOF-MS. HPLC analysis of self-prepared formulations indicated that by increasing the ratio of C. lanceolata, P. grandiflorum, and P. lobata in P. ginseng extracts, the peak area is increased at the same retention time. The limits of detection and quantification for lobetyolin and ononin were 0.098 and 0.171, and 0.108 and 0.726?mg/kg, respectively. Furthermore, the intraday precision (<1.0%) measurements confirmed that the developed analytical methods fulfill the required criteria for characterization of these products. The results demonstrated that the developed liquid chromatographic and mass spectrometric methods accurately characterized adulteration in P. ginseng commercial products.  相似文献   
160.
本文采用傅立叶变换红外光谱(吸收光谱、二阶导数谱及差谱)法对经不同剂量核辐照的人参粉进行了对比研究.辐照剂量不高于9 kGy时,人参粉样品的化学成分几乎没有发生变化;人参粉样品经15kGy及以上的辐照剂量辐照后,可能产生新的化学成分,表明采用辐照剂量不高于9 kGy的核辐照杀灭人参粉污染的微生物和各种寄生虫卵是可行的;...  相似文献   
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