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141.
为得到新型高效多相催化剂,有效去除废水中的染料,以Cu(Ac)_2与CuFe_2O_4@PDA为原料制备了催化剂CuFe_2O_4@PDA-Cu.通过IR、XRD、XPS、UV-Vis、DRS技术对催化剂的性能进行了表征,考察了温度、H_2O_2用量、催化剂用量、pH值、盐等对催化活性的影响.利用HPLC测定降解产物,采用自由基捕获和抑制实验进行机理验证,发现催化剂是核壳结构.温度升高、pH值升高、H_2O_2和催化剂用量的增加均有利于提高催化活性;氯化物、硫酸盐、硝酸盐和磷酸盐不影响催化效果,溴化物和亚硝酸盐降低了催化效果.得到的最优降解条件为:T=30℃,催化剂用量10mg·L~(-1),pH=9,过氧化氢用量10mmol·L~(-1),染料浓度30mg·L~(-1).最优条件下催化剂可循环使用4次以上;甲基橙、茜素红和罗丹明B的去除率为100%;染料R0213、O0118和B0115的去除率大于60%.降解产物有草酸、马来酸和CO_2.甲基橙、茜素红和罗丹明B降解后COD_(Mn)=2~4mg·L~(-1).水杨酸捕获·OH生成2.5-二羟基苯甲酸,叔丁醇抑制染料降解.结果表明,催化剂可活化H_2O_2产生·OH,·OH攻击染料分子开环降解直至矿化.该研究为开发高效多相催化剂,有效去除废水中的染料提供了科学依据. 相似文献
142.
143.
利用稳态和时间分辨瞬态光谱研究了有机盐trans-4-[p-(N-ethyl-N-(hydroxyethyl)amino)phenylstyryl]-N-(hydroxyethyl)pyridinium iodide (ASPI)掺杂聚合物PVK(聚乙烯咔唑)薄膜体系的光致发光和能量转移特性. 在ASPI:PVK掺杂薄膜体系中,PVK的荧光强度与寿命随掺杂浓度的升高而降低,表明两者存在有效的Forster能量转移. 通过在相对低浓度的掺杂体系中加入适量高量子效率的Alq3作为能量转移过渡体,形成能量转移级
关键词:
有机染料盐
荧光光谱
荧光寿命
能量转移 相似文献
144.
V. G. Balenko A. V. Kovtun A. N. Kirkin V. M. Mizin 《Journal of Applied Spectroscopy》2002,69(2):320-322
A new method is suggested for producing the solgel matrices with the molecules of laser dyes introduced into them. The curves of tuning lasing in Rhodamine 6G, Rhodamine 4S, Rhodamine 101, and phenylamine 430 in these matrices are obtained. The total range of tuning is 550–650 nm at a pumping energy of 4 mJ. The halfwidth of the generation spectrum is independent of the pumping energy to 4 mJ and comprises 0.3 ± 0.1 nm. The main factors forming the generation spectrum are noted. 相似文献
145.
将偶氮化合物乙基橙样品置于一对正交的偏振片之间,用一束激发光照射该样品,分别测量 在激发光的不同强度和不同偏振方向下探测光的透射功率,研究样品的双折射特性.实验表 明,透射光的饱和值和稳定值与激发光强成正比,且与激发光偏振方向有关,探测光与激发 光振动方向的夹角(θ)为45°时,其值最大;若θ不太小(>10°),sin22θ 与透射光的饱和值、稳定值成线性关系.同时,利用巴俾涅补偿器对样品的双折射率差进 行了测量,分别得到了绿光激发前后的准确数值为1.11×10-3和3.57×10 -3.
关键词:
偶氮
双折射
测量 相似文献
146.
Paramasivam Manisankar Subramanian Viswanathan Halliah Gurumallesh Prabu 《International journal of environmental analytical chemistry》2013,93(5):389-397
Electrochemical studies of direct orange 8 were carried out with a bare glassy carbon electrode (GCE) and a polypyrrole-coated GCE in aqueous acetonitrile medium using voltammetric techniques. One reversible couple around 0.3?V due to the redox reaction of the phenol group, one reduction peak around ?0.4?V due to reduction of the azo group and one oxidation peak around 1.0?V due to oxidation of the amino group were observed. Chronocoulometric studies revealed dye adsorption on the GCE. A square-wave stripping method was developed for the determination of the dye at pH 13.0, and a linear calibration equation obtained. The reproducibility in the measurement of peak currents was confirmed from the RSD value 2.8% at 0.001?mg?mL?1 concentration. A comparison of the stripping voltammetric method with the UV-Vis spectrophotometric method was made. The determination limits are wider and the RSD value is lower in the stripping voltammetric method. The concentration of the dye present in dye effluent was determined using this method. 相似文献
147.
The fluorescence properties of novel 6-butyl-2,3-dicyano-7-methyl-6H-1,4-diazepine styryl dyes having mono-, di-, tri-, and tetra(ethyleneglycol) units were examined. The mono(ethylenglycol) derivative was solid at room temperature, whereas the di-, tri-, and tetra(ethylenglycol) derivatives were oily. The monoethyleneglycol derivative showed weak aggregation-induced emission enhancement with fluorescence maximum at 649 nm, which comes from J-aggregates. The fluorescence of oily di-, tri-, and tetra(ethyleneglycol) derivatives in neat form was very weak. No aggregation-induced emission enhancement was observed for the oily derivatives. 相似文献
148.
Chiara Capolungo Dr. Damiano Genovese Prof. Marco Montalti Prof. Enrico Rampazzo Prof. Nelsi Zaccheroni Prof. Luca Prodi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(70):17529-17541
The growing numbers related to plastic pollution are impressive, with ca. 70 % of produced plastic (>350 tonnes/year) being indiscriminately wasted in the environment. The most dangerous forms of plastic pollution for biota and human health are micro- and nano-plastics (MNPs), which are ubiquitous and more bioavailable. Their elimination is extremely difficult, but the first challenge is their detection since existing protocols are unsatisfactory for microplastics and mostly absent for nanoplastics. After a discussion of the state of the art for MNPs detection, we specifically revise the techniques based on photoluminescence that represent very promising solutions for this problem. In this context, Nile Red staining is the most used strategy and we show here its pros and limitations, but we also discuss other more recent approaches, such as the use of fluorogenic probes based on perylene-bisimide and on fluorogenic hyaluronan nanogels, with the added values of biocompatibility and water solubility. 相似文献
149.
Ellis AL Christian Mason J Lee HW Strekowski L Patonay G Choi H Yang JJ 《Talanta》2002,56(6):1099-1107
Intracellular calcium concentration in biological cells varies from 0.1 to 10 μM depending upon cell signaling and disease states. A direct estimate of calcium concentration in cell tissues within this range is possible with a novel calcium-selective reagent 15C5-774. The molecule of 15C5-774 consists of a near-infrared (NIR) chromophore (λmax=774 nm) and a metal complexing moiety of benzo-15-crown-5. The reagent shows a strong calcium binding affinity in a 1:1 ratio and metal selectivity in the order Ca2+>Mg2+>Sr2+≈K+≈Na+>Zn2+>Li+. The high sensitivity is achieved by conducting absorption measurements in the NIR region where background interference from the biological matrix is low. 相似文献
150.
Although there exist a number of methods, such as NMR, X-ray, e.g., which explore the hydration of phospholipid bilayers,
the solvent relaxation (SR) method has the advantage of simple instrumentation, easy data treatment and possibility of measuring
fully hydrated samples. The main information gained from SR by the analysis of recorded “time-resolved emission spectra” (TRES)
is micro-viscosity and micro-polarity of the dye microenvironment. Based on these parameters, one can draw conclusions about
water structure in the bilayer. In this review, we focus on physical background of this method, on all the procedures that
are needed in order to obtain relevant parameters, and on the requirements on the fluorescence dyes. Furthermore, a few recent
applications (the effect of curvature, binding of antibacterial peptides and phase transition) illustrating the versatility
of this method are mentioned. Moreover, limitations and potential problems are discussed. 相似文献