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61.
Rufus Vinod Randa Mahran Erica Routila Janne Leivo Kim Pettersson Kamlesh Gidwani 《International journal of molecular sciences》2021,22(19)
Extracellular vesicles (EVs) are found in all biological fluids, providing potential for the identification of disease biomarkers such as colorectal cancer (CRC). EVs are heavily glycosylated with specific glycoconjugates such as tetraspanins, integrins, and mucins, reflecting the characteristics of the original cell offering valuable targets for detection of CRC. We report here on europium-nanoparticle (EuNP)-based assay to detect and characterize different surface glycoconjugates of EVs without extensive purification steps from five different CRC and the HEK 293 cell lines. The promising EVs candidates from cell culture were clinically evaluated on small panel of serum samples including early-stage (n = 11) and late-stage (n = 11) CRC patients, benign condition (n = 11), and healthy control (n = 10). The majority of CRC cell lines expressed tetraspanin sub-population and glycovariants of integrins and conventional tumor markers. The subpopulation of CD151 having CD63 expression (CD151CD63) was significantly (p = 0.001) elevated in early-stage CRC (8 out of 11) without detecting any benign and late-stage samples, while conventional CEA detected mostly late-stage CRC (p = 0.045) and with only four early-stage cases. The other glycovariant assays such as CEACon-A, CA125WGA, CA 19.9Ma696, and CA 19.9Con-A further provided some complementation to the CD151CD63 assay. These results indicate the potential application of CD151CD63 assay for early detection of CRC patients in human serum. 相似文献
62.
制备了稀土铕转光剂添加量分别为0.2%,0.5%,1.3%和2.0%(质量分数)的LDPE转光膜,测定了其在200~800 nm区间内的透射光谱。将LDPE转光膜用于橙味固体饮料的包装,并置于UV灯下进行照射,观察了其颜色变化。以橙味固体饮料的吸光度值作为变色指标,得到了吸光度值与UV灯光照时间的变化关系。结果表明,稀土铕转光剂添加量为1.3%的透明LDPE转光膜可作为该产品的包装材料,可使其颜色保持的时间最长。 相似文献
63.
64.
用已知化学纯度的两种浓缩同位素通过化学计量,配制人工合成样品,用来测量质谱计系统误差校正系数,校正用该仪器测量的来自地球不同地域矿样和试剂样品中锑(Sb)、铕(Eu)、铈(Ce)、铒(Er)四种元素天然同位素丰度比,求出这些元素同位素丰度的真值。用该真值和已知的上述四元素核素质量,计算得原子量分别为121.7597(7)Sb、151.9644(9)Eu、140.1157(8)Ce、167.2591(9)Er 相似文献
65.
溶胶-凝胶法制备的BaMgAl10O17:Eu前驱体的晶化过程 总被引:3,自引:0,他引:3
采用柠檬酸作为螯合物的溶胶-凝胶法制备了BaMgAl10O17:Eu(barium magnesium aluminate,BAM)蓝色荧光粉,并研究了,其晶化过程。通过X射线衍射、扫描电镜和荧光光谱等表征手段,研究了前驱体晶化过程的焙烧条件、结晶动力学、颗粒大小和发光性能等。BAM晶相在1100℃开始产生。温度达1200℃时,前驱体由无定型态完全转变成BAM晶相。在1120~1300℃时晶化反应的表观活化能为233kJ/mol。在室温下测得荧光粉的最大吸收峰和发射峰分别处在334nm和454nm。合成荧光粉的粒径为5μm左右,其形态和粒径取决于前驱体。 相似文献
66.
本文采用模板导向的方法,添加合适模板剂降低灼烧温度,合成橙红色荧光体。研究离子掺杂的荧光体Y2O3:Eu^3 A^m 、B^n 的荧光性质。发射光谱数据表明:杂质离子掺杂的荧光体Y2O3:Eu^3 A^m 、B^n 的荧光发射主峰与荧光体Y2O3:Eu^3 的荧光发射主峰(612nm)一致,为经典Eu^3 的^3D0-^7F2电偶极跃迁;杂质离子的引入明显地增强了Y2O3:Eu^3 的发光强度,并且有短时间余晖存在。 相似文献
67.
The subcellular localization of samarium and europium, two rare-earths, increasingly used in both medical and industrial fields, has been studied in several organs such as liver and kidney but never in the mammary gland despite of its importance in the biology of lactation and nutrition domains. The intracellular behaviour of samarium and europium after their intra-peritoneal administration in the lactating mammary gland cells was investigated. The results showed the presence of very electron dense deposits in the glandular epithelial cell lysosomes. These particular lysosomes were never observed in the mammary cell lysosomes of control rats. These intralysosomal deposits were probably composed of insoluble samarium or europium phosphates by analogy with previous studies, the transmission electron microscopy, the ion mass microscopy and the electron probe microanalysis, and other techniques allowing the identification of the chemical structure of the intralysosomal deposits. 相似文献
68.
Lanthanide fluorides exhibited unique luminescent properties in terms of their low phonon energy can restrict the luminescence quenching and extend luminescent lifetimes.Here,a room-temperature co-precipitation method was used to synthesize europium(III) activated La1-xGdxF3 solid phosphors.X-ray diffraction(XRD) data confirmed the crystalline phases of synthesized sample belongs to orthorhombic system.All the as-derived materials exhibited red luminescence(5D0→7F1) under the excitation at longer wavelengths(394 and 466 nm).The powder with the most intense emission was achieved in terms of 10 mol.% doping concentration(Eu content,La/Gd=1/9) and sample sintered at 700 oC.Scanning electron microscopy(SEM) investigated the morphology and crystalline of the samples,showing that many regular and large balls(5-10 μmol/L) were dispersed within the micro-meter scale composites.We proved that the above crystal growth structures were controllable and predicable based on the surface functionalization by polyvinylpyrrolidone ligand. 相似文献
69.
A ligand, 5-nitro-1,10-phenanthroline (phenNO2), was synthesized. Its Eu(III) complex with 2-thenoyltrifluoroacetone (HTTA) was prepared and characterized by elemental analysis, IR and 1H NMR spectra. The photophysical properties of the complex were studied in detail by using UV, luminescence spectra, luminescence lifetime and quantum yield. The complex exhibited nearly monochromatic red emission at 612 nm, a remarkable luminescence quantum yield at room temperature (36.0%) upon ligand excitation and a long 5D0 lifetime (458 μs), which indicated that the ligand phenNO2 could sensitize the luminescence of Eu(III) ion efficiently. 相似文献
70.
Batch adsorption experiments were conducted for the adsorption of Eu(III) ions from aqueous solution by D113 resin. The results indicated that D113 resin could adsorb Eu(III) ion effectively from aqueous solution. The adsorption was strongly dependent on pH of the medium with enhanced adsorption as the pH turned from 3.50 to 7.00 and the optimal adsorption condition was in HAc-NaAc medium with pH value of 6.50. The maximum uptake capacity of Eu(III) ions was 290.9 mg/g D113 at 298 K, at an initial pH value of 6.50. The overall adsorption process was best described by Lagergren-first-order kinetics. When Freundlich and Langmuir isotherms were tested, the latter had a better fit with the experimental data. The thermodynamic parameters such as free energy (?G) which were all negative, indicated that the adsorption of Eu(III) ions onto D113 resin was spontaneous and the positive value of enthalpy (?H) showed that the adsorption was endothermic in nature. Thomas model was applied to experimental column data to determine the characteristic parameters of column useful for process design. Furthermore, Eu(III) could be eluted by using 3.0 mol/L HCl solution and the D113 resin could be regenerated and reused. 相似文献