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991.
<正>Two haptens of 3-[(5-amino-furan-2-ylmethylene)amino]oxazolidin-5-one(FZ-NH_2) and 3-{[(4-carboxyphenyl)methylene]-amino} -2-oxazolidinone(CPAOZ) were synthesized.For FZ-NH_2,immunogens were prepared by glutaraldehyde and diazo salt methods.For CPAOZ,immunogens were connected by the methods of the active ester and mixed acid anhydride.Compared with the combination,indirect competitive enzyme-linked immunosorbent assay(ic-ELISA) was developed with coating antigen of FZ-NH_2 -OVA via the glutaraldehyde method and immunogen of CPAOZ-KLH via active ester method.For furazolidone and its metabolite AOZ(NPAOZ as derivative),the sensitivities(IC_(50)) were 2.0μg/L and 2.5μg/L,limits of detection(IC_(15)) were 0.09μg/L and 0.25μg/L,respectively.A sensitive method was developed for the simultaneous determination of furazolidone in feed and its metabolite AOZ in tissue.  相似文献   
992.
陈筱诚  余辉  郭娟  贺鹤勇  傅正文  龙英才 《化学学报》2010,68(21):2161-2166
以甲胺水溶液为改性剂, 高硅Y型沸石可在常温下吸附甲胺(MA)制备有机-无机杂化酸碱双功能高硅Y型沸石材料. X 射线粉末衍射(XRD), 固体29Si魔角核磁共振(13C及29Si MAS NMR)表征表明甲胺分子与高硅Y型沸石骨架相互作用导致沸石结构发生变化, 骨架上生成新的Si—N键及Si—OH. 以热重分析(TG/DTG), NH3, CO2程序升温脱附(NH3-TPD和CO2-TPD)研究杂化Y型沸石的酸碱性质及其经不同温度焙烧后的变化, 结果表明, 杂化后沸石的酸/碱量, 尤其是后者明显增大, 其原因是骨架上生成了新的Si—OH及Si—N键.  相似文献   
993.
994.
将水合碳酸铈与硝酸铝和氨水共同进行机械球磨,使新形成的无定型氢氧化铝包覆在细小的碳酸铈颗粒表面,经脱水干燥和煅烧,以制备出表面掺杂有氧化铝的氧化铈。结果表明:球磨中间产物仍然以水合碳酸铈为主,氢氧化铝的形成阻碍了碳酸铈的无定型化和向氢氧化铈的转化过程。在氧化铝掺杂量不超过10%的条件下,煅烧产物均具有立方萤石型结构。所有掺杂铝的氧化铈粉体对ZF7和K9光学玻璃的抛光速率均比纯氧化铈的有很大提高,证明铝的掺杂能够大大提高氧化铈的抛光性能。其最佳掺杂量为0.6%,煅烧条件为在1000℃下煅烧2 h。此时的MRR值为纯氧化铈的两倍以上。  相似文献   
995.
基于改进BP神经网络的煤催化气化预测模型研究   总被引:1,自引:0,他引:1  
采用改进的三层BP神经网络建立了煤催化气化反应失重率、气化初始温度和最大气化速率所对应温度的预测模型。结果表明,采用改进BP神经网络模型在此研究中可达到较高的精度,其最大预测误差分别为5.18% 、5.65% 、2.33%,明显小于归回公式的预测误差。
  相似文献   
996.
This work demonstrated the feasibility of detecting hydrocortisone in cosmetics using a novel CdSe/CdS quantum dots‐based competitive fluoroimmunoassay with magnetic core/shell Fe3O4/Au nanoparticles (MCFN) as solid carriers. Hydrocortisone antigen was labeled with the synthesized core/shell CdSe/CdS quantum dots (QDs) to form the antigen‐QDs conjugate. Meanwhile, hydrocortisone antibody was incubated with MCFN and the immobilized antibody was obtained. The immobilized antibody was then mixed sequentially with hydrocortisone and a slightly excess amount of the QDs‐labeled hydrocortisone antigen, allowing their competition for binding with the antibody immobilized on MCFN. The bound hydrocortisone and the antigen‐QDs conjugates on MCFN were removed subsequently after the mixture was applied to a magnetic force. The analyte concentration was obtained by measuring the fluorescence intensity of the unbound hydrocortisone antigen‐QDs conjugates. The proposed method was characterized by simplicity, rapidity, and high sensitivity with a wide linear working range of 0.5 to 15000 pg·mL?1 and a low detection limit of 0.5 pg·mL?1. The proposed method was successfully applied to the determination of hydrocortisone in cosmetics with satisfactory results.  相似文献   
997.
获取真实准确的蛋白质糖基化信息是全面了解糖基化修饰生物学功能的前提.针对简单蛋白质的糖基化分析通常采用反相高效液相色谱-串联质谱技术在肽的水平上对糖基化信息进行采集和解析.本文以人血清Alpha-1-酸性糖蛋白(AGP)酶解液为对象,发展了一套简单有效的蛋白质糖基化分析方法.本方法分为三个步骤,第一步是建立糖肽的理论m/z值表;第二步是获取糖蛋白酶解液的LC-MS谱图,并将每一个色谱峰中所包含糖肽的实际m/z值与理论m/z值进行人工匹配;第三步是对每个色谱峰的糖肽结构归属进行LC-MS/MS验证.采用本方法,我们从AGP酶解液中共鉴定出172条糖肽.与单独采用Survey模式的方法相比,本方法能够显著提高糖肽的覆盖率.  相似文献   
998.
蔡晓明  张岩  于龙  郭志谋  张秀莉  梁鑫淼 《色谱》2011,29(4):358-361
采用高效亲和色谱技术(HPAC)对中药成分与人血清白蛋白(HSA)的相互作用进行了研究。首先采用点击化学的方法制备了表面键合有HSA蛋白的硅胶固定相并装填成亲和色谱柱,根据药物在该色谱柱上与空白硅胶柱上的保留时间差计算得到药物与蛋白的结合率。利用该方法测得模型化合物华法令与HSA的结合率与文献中采用超滤法测得的结果基本一致,表明该方法可用于测定药物与HSA的结合率。在此基础上用该方法测定了葛根素和告依春两种中药成分与HSA的相对结合率分别为10.26%和10.20%。同时用超滤的方法测定了葛根素与HSA的结合率为14.25%。结果表明,HPAC可以作为研究药物与蛋白相互作用的一种简便可行的方法,其测定结果与超滤方法一致。  相似文献   
999.
Two novel copolymers based on squaraine and fluorine units have been synthesized through palladium catalyzed Suzuki coupling reaction and Sonogashira coupling reaction,respectively.The structures and properties of the two copolymers were characterized by FT-IR.NMR,UV-vis absorbance(Abs),gel permeation chromatography(GPC),thermal gravimetric analysis (TGA),differential scanning calorimetry(DSC) and cyclic voltammetry(CV).The solution absorption spectrums of P1 and P2 show two distinct absorption bands,one locates at 300-500 nm and the other at 600-800 nm.The absorption spectrums of P1 and P2 in films are broadened obviously and the spectral responses are extended up to 900 nm.Thermal gravimetric analysis demonstrates that the polymers are stable.Cyclic voltammetry experiment shows that the band gaps of the copolymers are 1.65 eV and 1.67 eV. respectively,suggesting their potential for applications as solar cells materials.  相似文献   
1000.
Li M  Li DW  Li YT  Xu DK  Long YT 《Analytica chimica acta》2011,701(2):157-163
A novel and facile hybrid analytical method coupling electrochemical “adsorption–desorption” and colorimetric analyses was developed to detect heavy metal ions in turbid water samples. The target metal ions were deposited onto an electrode inserted into the original sample, which was referred to as the “adsorption” process. After changing the medium, the concentrated target metal ions were dissolved in a new, clean buffer (blank buffer), which was referred to as the “desorption” process. The concentrations of the target metal ions were measured by colorimetric analyses after the addition of specific indicator amounts. We demonstrated the applicability of this method by detecting Cd2+, Pb2+ and Cu2+ with co-depositing Bi3+ on portable screen-printed electrodes (SPEs). A good correlation (correlation coefficient of R = 0.997) was observed between concentrations ranging from 1 to 200 μM and absorbance values. After the multiple “desorption” process, the even better detection limits as low as 10, 10 and 100 nM were achieved for Cd2+, Pb2+ and Cu2+, respectively. The practicality of this hybrid method was confirmed by the detection of Cd2+, Pb2+ and Cu2+ in wastewater samples, and these results were in agreement with inductively coupled plasma atomic emission spectroscopy (ICP-AES). Overall, this hybrid method provides a simple, selective and effective technique for environmental pollutant analyses.  相似文献   
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