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991.
在CaCl2.H2O和Na2C2O4配制的过饱和溶液中,利用L-半胱氨酸(L-Cys)在金片上形成的自组装膜为模板,研究了草酸钙(CaOxa)在自组装膜上的结晶行为,并探讨了溶液pH对CaOxa晶体组成、晶型及其形貌的影响。采用X射线衍射(XRD)和扫描电子显微镜(SEM)等技术对CaOxa晶体的结构和形貌进行了表征。实验结果表明:当溶液pH=3.0时,溶液中可以形成一水草酸钙(CaC2O4.H2O,COM)和二水草酸钙(CaC2O4.2H2O,COD)晶体,而在同样pH条件下,在L-Cys自组装膜上只形成COD晶体,表明自组装单层对CaOxa晶体的成核和生长有重要影响。通过改变溶液的pH,在自组装单层上可以得到不同晶型和不同形状的CaOxa晶体。当pH=3.0时得到四方块状的COD晶体,而pH=5.0和pH=7.0时分别得到六边形和拉长六边形的COM晶体。 相似文献
992.
P. C. Schulz R. M. Minardi M. E. Gschaider de Ferreira B. Vuano 《Colloid and polymer science》1998,276(1):52-58
The air/water interface of the system n-dodecanephosphonic acid (H2DP)–water was studied by surface tension, ion-selective electrodes and evaporation in an electrobalance. The combination of
surface tension and ion-selective electrodes measurements enables to study the adsorption of soluble surfactants above the
cmc using the Gibbs’ equation. H2DP formed a nonideal monolayer at the air/water interface with A
molec=0.995 nm2 below the cmc. Above the cmc there was a reduction in adsorption giving A
molec=6.32 nm2, which remained almost constant in the explored concentration range. This adsorption reduction may be due to a change composition
on micellization, or to a thermodynamic advantage of micellization on adsorption. The reduction in the evaporation rate of
water was mainly due to the reduction of the water activity, caused by the presence of solutes in bulk. This is because the
strong changes in the surface coverage did not have significant influence on the evaporation rate.
Received: 6 January 1997 Accepted: 15 August 1997 相似文献
993.
硅表面有机单层膜 :微印章、微加工与微阵列 总被引:1,自引:0,他引:1
总结了作者的实验室在将有机物结合到硅表面方面的研究进展.发现并发展了将有机单层膜组装到硅、氧化硅和相关材料表面的新方法.这些方法简单、可重复,并可得到物理、化学性能良好的致密单层膜.这些单层膜在许多方面有令人鼓舞的应用,包括(a)应用于软印刷术,特别是微接触印章法; (b)用作硅的微加工(微机电系统,MEMS)的单层膜润滑剂; (c)用作DNA和蛋白质微阵列功能分子固定的基底. 相似文献
994.
Minsu Lee Youngjune Hur Taeil Kim Kyungho Kim Jaeho Kim Heungjin Choi Kwangnak Koh 《Microchemical Journal》2002,72(3):1608-321
Phenylboronic acid derivatives were synthesized and their self-assembled monolayers (SAMs) were formed on a gold surface. The interaction between fructose and phenylboronic acid monolayers was evaluated using surface plasmon resonance (SPR). These phenylboronic acid monolayers showed good sensitivity to fructose at a low concentration range and the resonance angle shifts increased in accordance with the alkyl chain length. 相似文献
995.
A new human ferritin immunosensor was developed using anti-human ferritin antibodies (Abs) immobilized on the gold disc of a quartz crystal microbalance (QCM). Two kinds of self-assembled monolayers (SAMs) prepared by cystamine-glutaraldehyde and cystamine method were applied to immobilize anti-ferritin monoclonal antibodies (MoAbs) and polyclonal antibodies (PoAbs) on the quartz, respectively. The reusabilities of quartz crystal adopting the SAMs were found to be better than those of the other immobilization methods used. The 10 cycles of measurements could be performed on the gold surface of the same crystal regenerated with a solution of glycine·HC1. This sensor system could be continuously performed for 15 days, the relative frequency shifts (the frequency shifts measured are relative to the response at the first day) were all found to be above 95%. A linear relationship existed between the frequency shifts (Hz) and the log values of human ferritin concentrations in the range from 0.1 to 100 ng/ml in buffer and mouse serum. This human ferritin immunosensor had some advantages: high sensitivity, high specificity, low sample requirement, high reusability, no label and no pretreatment etc. 相似文献
996.
新型壳聚糖基自组装纳米胶束紫杉醇药物释放载体 总被引:3,自引:0,他引:3
以N-胆甾醇琥珀酰基-O-羧甲基壳聚糖(CCMC, 胆甾醇基取代度6.9%)为原料, 在水溶液中通过探头超声处理制备其自组装凝胶纳米胶束, 采用稳态荧光探针法考察临界胶束浓度, 并通过透射电镜和动态激光散射仪检测胶束的形态大小. 以紫杉醇为模型药物, 采用透析法制备载药CCMC纳米胶束, 并通过高效液相色谱法(HPLC)考察其在纳米胶束中的包载及释放情况. 结果显示, CCMC为两亲性高分子, 在水溶液中能形成粒径为198.4 nm的规则球状胶束, 临界胶束浓度为0.018 mg/mL. 紫杉醇顺利包载于CCMC-纳米胶束内, 载药量高达34.9%; 随着载药量的增加, 胶束粒径呈增大的趋势. 体外释放实验结果显示, CCMC纳米胶束能延缓紫杉醇的释放, 释药速度和释放介质pH值密切相关. 相似文献
997.
998.
999.
A simple and highly specific protein detection system using glycoconjugated gold nanoparticles was investigated. This system
was based on the aggregation of gold nanoparticles coated with carbohydrate alkanethiols in the presence of corresponding
proteins (lectins) that had specific recognition for certain carbohydrates. In order to construct an efficient specific recognition
system, maltoside alkanethiol was adopted as an effective sensing modifier having a disaccharide group and a flexible long
alkyl chain. The surface modification of gold nanoparticles with maltoside alkanethiol resulted in a shift and broadening
(from 520 to 610 nm) of the absorption peak. Monodispersed maltoside-adsorbed gold nanoparticles aggregated with the specific
lectin, concanavalin A (Con A). This phenomenon was used to detect the presence of Con A and to estimate concentrations of
Con A in sample solutions. The precipitate of the maltoside–gold nanoparticle–Con A mixture was redispersed by addition of
methyl α-D-mannopyranoside whose adsorption coefficient is larger than that of maltoside with Con A. 相似文献
1000.
纯Y型硬脂酸铅LB膜的制备及结构表征 总被引:1,自引:0,他引:1
纯Y型硬脂酸铅LB膜的制备及结构表征陈海燕,彭笑刚,于连香,周勇亮,姜月顺,李铁津(吉林大学化学系,长春,130023)徐跃,高忠民,魏诠(吉林大学测试中心)关键词硬脂酸铅,LB膜转移,硫化铅单层膜在脂肪酸盐LB膜的沉积过程中,存在由Y型向X型沉积的... 相似文献