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41.
Obesity is a foremost health issue that affects about 1.6 million people out of which 400 million worldwide. Epidemiological evidences prove obesity is the primary cause for various metabolic ailments e.g. diabetes. Poria cocos possess extensive biological actions, for instance, antioxidant, anti-inflammatory, antitumor, immunomodulatory actions. The primary limitation of all phytomedicine was their poor bioavailability hence in this investigation, we bio-fabricated the gold nanoparticles from Poria cocos aqueous extract and inspected their potency to treat obesity. Obese rat model were produced via fed the young female rats with high fat food for 8 weeks regimen. Further to confirm the potency of Poria cocos gold nanoparticles against obesity induced metabolic disorders we treated obese rats with low dose streptozotocin in the conclusion of the investigational time. The synthesis of Poria cocos gold-nanoparticles was evidenced via the UV-Spectroscopic study and characterized with SEM, TEM and EDAX studies. The anti-obesity actions of Poria cocos gold-nanoparticles were investigated by estimating the glucose profile, kidney markers, lipid profile, inflammatory cytokines, adipocyte markers, antioxidants in the Poria cocos gold nanoparticles treated obese rats. To confirm the Poria cocos gold nanoparticles role on inhibiting the obesity induced metabolic disorders we analyzed the histopathological changes in cardiac tissues. Our physical characterization confirms the synthesized Poria cocos gold nanoparticles assure the distinctions of influential nanoparticles to be utilized for the treatment. The results from biochemical and histopathological analysis confirms Poria cocos gold nanoparticles is a persuasive antidiabetic, anti-inflammatory, antioxidant, anti-obesity drug. Overall our results authentically confirm Poria cocos gold nanoparticles is a potent anti-obesity drug and it also protects from obesity induced metabolic disorders.  相似文献   
42.
A capillary zone electrophoretic method with UV-scanning detection for the separation and identification of both free ligands and metal species is presented. The electrophoretic behavior of naturally occurring binding partners such as organic acids and amino acids was studied and compared with their metal-complexes. Copper(II) complexes of citrate and amino acids showed decreased electrophoretic mobilities and altered UV spectra. The optimized method was validated on ultrafiltered cow's milk and human milk samples. In cow's milk six low molecular weight substances, including citrate, orotate, and hippurate, could be separated. Metal supplementation with Cu(II), Ni(II), or Zn(II) decreased not only the citrate peak but also the orotate signal and in the case of copper(II) supplementation a new signal for the copper(II)-citrate complex appeared. In human milk samples various amino acids such as glutamate, phenylalanine, tyrosine, and tryptophan could be identified besides citrate. The electrophoretic mobilites and peak areas of the amino acids were also influenced by the metal supplementation.  相似文献   
43.
Poor water solubility and low bioavailability of hydrophobic flavonoids such as rutin remain as substantial challenges to their oral delivery via functional foods. In this study, the effect of pH and the addition of a protein (sodium caseinate; NaCas) on the aqueous solubility and stability of rutin was studied, from which an efficient delivery system for the incorporation of rutin into functional food products was developed. The aqueous solubility, chemical stability, crystallinity, and morphology of rutin (0.1–5% w/v) under various pH (1–11) and protein concentrations (0.2–8% w/v) were studied. To manufacture the concentrated colloidally stable rutin–NaCas particles, rutin was dissolved and deprotonated in a NaCas solution at alkaline pH before its subsequent neutralisation at pH 7. The excess water was removed using ultrafiltration to improve the loading capacity. Rutin showed the highest solubility at pH 11, while the addition of NaCas resulted in the improvement of both solubility and chemical stability. Critically, to achieve particles with colloidal stability, the NaCas:rutin ratio (w/w) had to be greater than 2.5 and 40 respectively for the lowest (0.2% w/v) and highest (4 to 8% w/v) concentrations of NaCas. The rutin–NaCas particles in the concentrated formulations were physically stable, with a size in the range of 185 to 230 nm and zeta potential of −36.8 to −38.1 mV, depending on the NaCas:rutin ratio. Encapsulation efficiency and loading capacity of rutin in different systems were 76% to 83% and 2% to 22%, respectively. The concentrated formulation containing 5% w/v NaCas and 2% w/v rutin was chosen as the most efficient delivery system due to the ideal protein:flavonoid ratio (2.5:1), which resulted in the highest loading capacity (22%). Taken together, the findings show that the delivery system developed in this study can be a promising method for the incorporation of a high concentration of hydrophobic flavonoids such as rutin into functional foods.  相似文献   
44.
利用自行设计的反应器研究了高温条件下水蒸汽对无水五硼酸钾晶体结构的影响,借助于X射线衍射、红外光谱、Raman光谱等手段分析了无水五硼酸钾晶体高温性质的振动光谱。在水蒸汽的作用下,五硼酸钾的B2O3/K2O(摩尔比)变小,X射线衍射分析表明750 ℃时晶体中有K5B19O<sub>31存在,而红外光谱与Raman光谱分析表明由于水蒸汽的作用使得晶体中的三角形B(3)—O结构单元向四面体B(4)—O结构单元转变,四面体的B(4)—O含量增加并且硼氧网络结构被进一步打断。  相似文献   
45.
曲栗  古淑青  张嘉麒  赵超敏  邓晓军 《色谱》2021,39(5):472-477
近年来羊奶粉和骆驼奶粉备受消费者青睐,它们具有潜在的低致敏性,因此成为牛乳不耐受人群尤其是婴幼儿的母乳替代品,其营养价值备受关注.牛奶粉、羊奶粉和骆驼奶粉中氨基酸含量的比较研究鲜有报道.利用酸水解得到游离氨基酸,选择6-氨基喹啉-N-羟基琥珀酰亚胺氨基甲酸酯(AQC)进行柱前衍生,超高效液相色谱分离并检测,外标法定量....  相似文献   
46.
In recent times, consumers have shown increasing interest in plant substitutes for fermented dairy products. This study aimed to investigate the properties of yogurt-type rice-based beverages fermented with lactic acid bacteria and Propionibacterium. The changes in pH, viable population of bacteria, physical properties, and carbohydrate content of these beverages were tested. Fermentation using only Propionibacterium was insufficient to obtain a product with an acidity level similar to that of milk-based yogurt (pH < 4.5). After fermentation, the tested beverages had a high number of Lactobacillus sp. (7.42–8.23 log10 CFU/mL), Streptococcus thermophilus (8.01–8.65 log10 CFU/mL), and Bifidobacterium animalis subsp. lactis (8.28–8.50 log10 CFU/mL). The hardness (2.90–10.40 N) and adhesiveness (13.79–42.16 mJ) of the samples after 14 days of storage at 6 °C varied depending on the starter culture used. The syneresis of all samples ranged between 29% and 31%, which was lower or close to that of milk-based yogurts. The content of individual sugars in the samples also varied depending on the starter culture used for fermentation. The results suggest that the combination of lactic and propionic fermentation helps in the production of rice-based yogurt-type milk substitutes.  相似文献   
47.
This paper proposes the use of the least-squares support vector machine (LS-SVM) as an alternative multivariate calibration method for the simultaneous quantification of some common adulterants (starch, whey or sucrose) found in powdered milk samples, using near-infrared spectroscopy with direct measurements by diffuse reflectance. Due to the spectral differences of the three adulterants a nonlinear behavior is present when all groups of adulterants are in the same data set, making the use of linear methods such as partial least squares regression (PLSR) difficult. Excellent models were built using LS-SVM, with low prediction errors and superior performance in relation to PLSR. These results show it possible to built robust models to quantify some common adulterants in powdered milk using near-infrared spectroscopy and LS-SVM as a nonlinear multivariate calibration procedure.  相似文献   
48.
本文介绍了进口棕榈油中的脂肪酸的色-质联用分析方法。其中,特别检测了油中的奇碳数脂肪酸,并和其它食用油中的脂肪酸作了比较。  相似文献   
49.
建立了用于检测牛奶和奶粉中拉沙洛菌素、莫能菌素、尼日利亚菌素、盐霉素、甲基盐霉素和马杜霉素铵6种聚醚类抗生素残留量的超高效液相色谱-串联质谱分析方法.用乙腈提取样品中的聚醚类抗生素,提取液经HLB固相萃取柱净化,采用超高效液相色谱分离,以电喷雾离子源正离子多反应监测模式进行质谱分析.6种抗生素在0.5~100.0 μg/L范围内均呈线性,相关系数r>0.99.在空白样品中添加6种聚醚类抗生素的回收率均在74.0%~98.5%之间; 精密度(RSD)4.8%~17.2%.牛奶中6种聚醚类抗生素检出限均为0.2 μg/L;奶粉中6种聚醚类抗生素检出限均为1.6 μg/kg.  相似文献   
50.
建立了液相色谱-串联质谱法同时测定动物脂肪中111种农药残留的分析方法.样品经乙腈均质提取2次,旋转蒸发浓缩后经过凝胶渗透色谱净化.111种农药在Atlantis T3柱上以乙腈和0.1%甲酸溶液为流动相,梯度洗脱条件下完成分离,采用电喷雾电离串联质谱在正离子多反应监测模式下进行测定.目标化合物的保留时间为2.4 ~33.8 min,线性相关系数为0.984 5 ~0.999 9;在4种动物脂肪中分别添加1倍、2倍、4倍定量下限3个水平的平均回收率为60% ~120%,相对标准偏差为0.6% ~19.8%;111种农药在动物脂肪中的检出限为0.20 ~960 μg/kg,定量下限为0.40 ~2 400 μg/kg.该方法操作简单、灵敏度高、选择性好,符合农药多残留分析的要求.  相似文献   
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