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901.
Mustapha Muhammad Nasiru Muhammad Umair Evans Frimpong Boateng Fawze Alnadari Kashif-ur Rehman Khan Zhaobin Wang Ji Luo Wenjing Yan Hong Zhuang Ali Majrashi Jianhao Zhang Sameh A. Korma 《Molecules (Basel, Switzerland)》2022,27(3)
Egg white protein (EWP) is susceptible to denaturation and coagulation when exposed to high temperatures, adversely affecting its flavour, thereby influencing consumers’ decisions. Here, we employ high-voltage cold plasma (HVCP) as a novel nonthermal technique to investigate its influence on the EWP’s flavour attributes using E-nose, E-tongue, and headspace gas-chromatography-ion-mobilisation spectrometry (HS-GC-IMS) due to their rapidness and high sensitivity in identifying flavour fingerprints in foods. The EWP was investigated at 0, 60, 120, 180, 240, and 300 s of HVCP treatment time. The results revealed that HVCP significantly influences the odour and taste attributes of the EWP across all treatments, with a more significant influence at 60 and 120 s of HVCP treatment. Principal component analyses of the E-nose and E-tongue clearly distinguish the odour and taste sensors’ responses. The HS-GC-IMS analysis identified 65 volatile compounds across the treatments. The volatile compounds’ concentrations increased as the HVCP treatment time was increased from 0 to 300 s. The significant compounds contributing to EWP characterisation include heptanal, ethylbenzene, ethanol, acetic acid, nonanal, heptacosane, 5-octadecanal, decanal, p-xylene, and octanal. Thus, this study shows that HVCP could be utilised to modify and improve the EWP flavour attributes. 相似文献
902.
Hui Wang Mingyong Zhang Jiahao Fang Yuzhen He Min Liu Zhanying Hong Yifeng Chai 《Molecules (Basel, Switzerland)》2022,27(3)
Salvia miltiorrhiza Bunge (SM) has been extensively used in Alzheimer’s disease treatment, the permeability through the blood-brain barrier (BBB) determining its efficacy. However, the transport mechanism of SM components across the BBB remains to be clarified. A simple, precise, and sensitive method using LC-MS/MS was developed for simultaneous quantification of tanshinone I (TS I), dihydrotanshinone I (DTS I), tanshinone IIA (TS IIA), cryptotanshinone (CTS), protocatechuic aldehyde (PAL), protocatechuic acid (PCTA), and caffeic acid (CFA) in transport samples. The analytes were separated on a C18 column by gradient elution. Multiple reaction monitoring mode via electrospray ionization source was used to quantify the analytes in positive mode for TS I, DTS I, TS IIA, CTS, and negative mode for PAL, PCTA, and CFA. The linearity ranges were 0.1–8 ng/mL for TS I and DTS I, 0.2–8 ng/mL for TS IIA, 1–80 ng/mL for CTS, 20–800 ng/mL for PAL and CFA, and 10–4000 ng/mL for PCTA. The developed method was accurate and precise for the compounds. The relative matrix effect was less than 15%, and the analytes were stable for analysis. The established method was successfully applied for transport experiments on a BBB cell model to evaluate the apparent permeability of the seven components. 相似文献
903.
904.
Xiaoxiao Qu Weiwei Kang Changwei Lai Chuanxiang Zhang Suck Won Hong 《Molecules (Basel, Switzerland)》2022,27(3)
High-performance porous carbons derived from tea waste were prepared by hydrothermal treatment, combined together with KOH activation. The heat-treatment-processed materials possess an abundant hierarchical structure, with a large specific surface of 2235 m2 g−1 and wetting-complemental hydrophilicity for electrolytes. In a two-electrode system, the porous carbon electrodes’ built-in supercapacitor exhibited a high specific capacitance of 256 F g−1 at 0.05 A g−1, an excellent capacitance retention of 95.4% after 10,000 cycles, and a low leakage current of 0.014 mA. In our work, the collective results present that the precursor crafted from the tea waste can be a promising strategy to prepare valuable electrodes for high-performance supercapacitors, which offers a practical strategy to recycle biowastes into manufactured materials in energy storage applications. 相似文献
905.
Ganesh Shenoy Jessica Ettedgui Chandrasekhar Mushti Jennifer Hong Kelly Lane Burchelle Blackman Hak-Sung Jung Yasuharu Takagi Yeonee Seol Martin Brechbiel Rolf E. Swenson Keir C. Neuman 《Molecules (Basel, Switzerland)》2022,27(3)
Carboxylic acid is a commonly utilized functional group for covalent surface conjugation of carbon nanoparticles that is typically generated by acid oxidation. However, acid oxidation generates additional oxygen containing groups, including epoxides, ketones, aldehydes, lactones, and alcohols. We present a method to specifically enrich the carboxylic acid content on fluorescent nanodiamond (FND) surfaces. Lithium aluminum hydride is used to reduce oxygen containing surface groups to alcohols. The alcohols are then converted to carboxylic acids through a rhodium (II) acetate catalyzed carbene insertion reaction with tert–butyl diazoacetate and subsequent ester cleavage with trifluoroacetic acid. This carboxylic acid enrichment process significantly enhanced nanodiamond homogeneity and improved the efficiency of functionalizing the FND surface. Biotin functionalized fluorescent nanodiamonds were demonstrated to be robust and stable single-molecule fluorescence and optical trapping probes. 相似文献
906.
907.
在细胞色素C催化下,吡啰红B与青蒿素反应导致荧光降低,细胞色素C与青蒿素的反应为酶-底物模型。动力学研究表明,稳态催化速率依赖于酶和底物浓度,催化常数Km、Vm ax及Kcat分别为3.3×10-5mol/L,5.4×10-6mol.L-1.s-1和13.5 s-1,催化活性受去活化剂和乙醇抑制。在pH 5.3、25℃及7.6×10-7mol/L的细胞色素C催化条件下,荧光降低值ΔF(F0-F)与青蒿素浓度在7.1×10-8~1.1×10-6mol/L范围内呈线性关系;检出限为7.2×10-9mol/L;加标回收率为96.3%~106.8%。方法已用于测定血浆和尿液介质中的微量青蒿素。 相似文献
908.
909.
碱木素的近红外光谱吸收机理的研究 总被引:1,自引:1,他引:0
通过碱木素模型物对醌、邻醌和香兰素的溶液在800~900 nm的近红外光谱波段内的吸收谱图的对比发现,对醌和邻醌在此波段产生较强的吸收,而香兰素基本上没有吸收,证明了碱木素的醌型结构在800~900 nm波段内产生特征吸收。对银杏和夹竹桃磨木木素碱处理前后的溶液在800~900 nm波段内的吸光度的差别分析,发现夹竹桃的磨木木素的吸光度的相对变化更大,这是由于夹竹桃磨木木素经碱处理后产生了更多的醌型结构。这也是在硫酸盐法蒸煮过程中在800~900 nm波段内阔叶材的蒸煮液吸光度大于针叶材的蒸煮液吸光度的主要原因。 相似文献
910.
天然气管道泄漏可调谐二极管激光遥感探测的研究 总被引:2,自引:0,他引:2
天然气管道泄漏不仅造成经济损失而且是危险之源。传统的天然气管道泄漏检测技术效率低、速度慢,难以满足实际应用的需要。近年来以近红外二极管激光吸收光谱为基础的光学传感器由于具有灵敏度高、体积小、重量轻和无需维护等优点而得到了广泛的应用。文章以可调谐二极管激光吸收光谱和谐波探测技术为基础进行天然气管道泄漏遥感探测技术的研究,采用二次谐波与一次谐波信号的比值作为系统浓度标定,结果显示浓度与比值之间具有较好的一致性。文章还就不同地形散射体对探测结果的影响进行了测量和分析,实验结果表明二次谐波与一次谐波信号比值标定技术对便携式二极管激光光学测量能够很好的满足实际应用的需要。 相似文献