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1.
Current forensic DNA profiles are obtained based on analyses of PCR product sizes or DNA sequence polymorphisms. Sometimes routine forensic analysis using short tandem repeat (STR) generates unsuccessful DNA testing result if the biological sample encountered is excessively degraded and low-template DNA. Herein, a new six-color fluorescence labeling system, including 59 autosomal diallelic deletion or insertion polymorphisms (DIPs), 2 miniSTRs, 2 Y-chromosome DIPs, and 1 Amelogenin gene with the amplicon sizes of less than 200 bp, was self-developed. According to the validation guidelines for DNA analysis methods formulated by the Scientific Working Group on DNA Analysis Methods, the validation studies have also been carried out for the multiplex system. This novel panel possessed the features of strong stability, high sensitivity, and good specificity, which was especially suitable for the forensic degraded and mixed sample detections. The cumulative power of exclusion and cumulative matching probability of the system were 0.9999978 and 9.833E-28, respectively, in Han Chinese in Hunan, China. Moreover, this system will be an effective new tool that can be independently applied to forensic personal identification and paternity testing in the populations from the East Asia region, even from the South Asia, America, and Europe regions. The system can also contribute to population phylogenetic affinity and genetic structure analyses among different populations. 相似文献
2.
Menel Ben Frej Fanny d'Orlyé Gerson F. Duarte-Junior Wendell K. T. Coltro Anne Varenne 《Electrophoresis》2022,43(20):2044-2048
A low-cost and straightforward hybrid NOA (Norland optical adhesive) 81-glass microchip electrophoresis device was designed and developed for protein separation using indirect fluorescence detection. This new microchip was first characterized in terms of surface charge density via electroosmotic mobility measurement and stability over time. A systematic determination of the electroosmotic mobility (μeo) over a wide pH range (2–10) and at various ionic strengths (20–50 mM) was developed for the first time via the neutral marker approach in an original simple frontal methodology. The evolution of μeo was proved consistent with the silanol and thiol functions arising from the glass and the NOA materials, respectively. The repeatability and reproducibility of the measurements on different microchips (RSD < 14%) and within 15 days (less than 5% decrease) were successfully demonstrated. The microchip was then applied for the efficient electrophoretic separation of proteins in a zonal mode coupled with indirect fluorescence detection, which is, to our knowledge, the first proof of concept of capillary zone electrophoresis in this hybrid microsystem. 相似文献
3.
通过Knoevenagel缩合反应制备了一个具有溶酶体靶向的近红外光敏剂IMBDP-Lys, 用于双光子荧光成像和光动力治疗. IMBDP-Lys由2个吲哚吗啉功能团连接到氟硼二吡咯(BODIPY)母核的3?位和8?位构筑而成, 是一种重原子诱导的光敏剂. 采用高斯09W理论计算光敏剂S1态和T2态能量值相差0.12 eV, 可以有效地发生系间窜越. 在二氯甲烷溶液中, 光敏剂IMBDP-Lys的最大吸收波长为631 nm, 最大发射波长为684 nm. 在 660 nm的光照下, 以亚甲基蓝为参比, 单线态氧量子产率经计算为48.3%. 此外, 含有2个吗啉基团的光敏剂IMBDP-Lys具有良好的生物相容性和精准的靶向能力, 可以快速地进入斑马鱼体内进行双光子荧光成像, 并且与溶酶体绿色染料Lyso-Tracker Green共定位系数为0.95. 溴化噻唑蓝四氮唑(MTT)实验结果表明, 光敏剂具有低的暗毒性(≥85%)和高的光毒性(IC50=0.52 μmol/L). 在660 nm的光照下, 利用活性氧荧光探针2’,7’-二氯二氢荧光素二乙酸酯(DCFH-DA)证明光敏剂可以产生活性氧, 同时吖啶橙/溴化乙锭(AO/EB)染色实验和细胞迁移实验表明产生的活性氧不仅能诱导A549细胞凋亡, 还能有效地抑制肿瘤细胞迁移. 因此, 近红外光敏剂IMBDP-Lys在双光子荧光成像和溶酶体靶向的光动力治疗中具有重要的应用价值. 相似文献
4.
Zhihong Zhao Bin Wang Rui Tan Wenjing Liu Minghui Zhang 《Magnetic resonance in chemistry : MRC》2022,60(4):427-433
In this study, the transverse relaxation time (T2) of activated carbon (AC) in different relative environment humidity was detected firstly by low-field nuclear magnetic resonance (LFNMR). The pore size (diameter) of AC distributions was calculated by the relationship between T2 and surface relaxation rate (ρ), where ρ was obtained by the detection of nine porous materials with known pore size. The results showed that the pore size distributions of AC calculated by ρ < 0.19 nm/ms were in good agreement with that obtained by nitrogen adsorption method and proved that LFNMR as a new detection method was feasible for characterizing AC pore size distribution. 相似文献
5.
6.
Xianghao Luo Anqi Tian Mengyu Pei Dr. Jiaying Yan Dr. Xiang Liu Prof. Long Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(3):e202103361
With the development of green chemistry, it is still a challenge to maintain the unstable valence state of the metal in heterogeneous catalysts and realize new catalytic synthesis methods. In this paper, it is reported that an univalent copper nanocomposite (Cu@Al/SBA-15) can efficiently catalyze the formation of novel amino-containing benzotriazoles with great fluorescence properties in a new synthetic strategy. Subsequently, its application is further verified by an acylation reaction to produce a series of novel benzotriazoles derivatives with high yield. It is worth noting that the Cu@Al/SBA-15 nanocomposites not only enable the reaction completed with high yield in a short time, but can also be recycled many times without a significant reduction in activity, and the leaching of copper and aluminum species in reaction system is negligible. Finally, the detailed and feasible reaction mechanism is also provided. 相似文献
7.
Dr. Shengjun Yang Philip Saul Salvatore Mamone Dr. Lukas Kaltschnee Dr. Stefan Glöggler 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(8):e202104158
Bimodal molecular probes combining nuclear magnetic resonance (NMR) and fluorescence have been widely studied in basic science, as well as clinical research. The investigation of spin phenomena holds promise to broaden the scope of available probes allowing deeper insights into physiological processes. Herein, a class of molecules with a bimodal character with respect to fluorescence and nuclear spin singlet states is introduced. Singlet states are NMR silent but can be probed indirectly. Symmetric, perdeuterated molecules, in which the singlet states can be populated by vanishingly small electron-mediated couplings (below 1 Hz) are reported. The lifetimes of these states are an order of magnitude longer than the longitudinal relaxation times and up to four minutes at 7 T. Moreover, these molecules show either aggregation induced emission (AIE) or aggregation caused quenching (ACQ) with respect to their fluorescence. In the latter case, the existence of excited dimers, which are proposed to use in a switchable manner in combination with the quenching of nuclear spin singlet states, is observed 相似文献
8.
Georgia Ivanova Nadezhda Bozova Nikolay Petkov Dr. Cunbin An Dr. Benlin Hu Monika Mutovska Konstantin Konstantinov Dr. Yulian Zagranyarski Dr. Vladimira Videva Adelina Yordanova Prof. Martin Baumgarten Prof. Anela Ivanova 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(16):e202104411
Computational modeling of the optical characteristics of organic molecules with potential for thermally activated delayed fluorescence (TADF) may assist markedly the development of more efficient emitting materials for organic light-emitting diodes. Recent theoretical studies in this area employ mostly methods from density functional theory (DFT). In order to obtain accurate predictions within this approach, the choice of a proper functional is crucial. In the current study, we focus on testing the performance of a set of DFT functionals for estimation of the excitation and emission energy and the excited singlet-triplet energy gap of three newly synthesized compounds with capacity for TADF. The emitters are designed specifically to enable charge transfer by π-electron conjugation, at the same time possessing high-energy excited triplet states. The functionals chosen for testing are from various groups ranging from gradient-corrected through global hybrids to range-separated ones. The results show that the monitored optical properties are especially sensitive to how the long-range part of the exchange energy is treated within the functional. The accurate functional should also be able to provide well balanced distribution of the π-electrons among the molecular fragments. Global hybrids with moderate (less than 0.4) share of exact exchange (B3LYP, PBE0) and the meta-GGA HSE06 are outlined as the best performing methods for the systems under study. They can predict all important optical parameters correctly, both qualitatively and quantitatively. 相似文献
9.
Paul T. Ludford III Shenghua Yang Marcela S. Bucardo Prof. Yitzhak Tor 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(13):e202104472
A new fluorescent ribonucleoside alphabet (mthN) consisting of pyrimidine and purine analogues, all derived from methylthieno[3,4-d]pyrimidine as the heterocyclic core, is described. Large bathochromic shifts and high microenvironmental susceptibility of their emission relative to previous alphabets derived from thieno[3,4-d]pyrimidine (thN) and isothiazole[4,3-d]pyrimidine (tzN) scaffolds are observed. Subjecting the purine analogues to adenosine deaminase, guanine deaminase and T7 RNA polymerase indicate that, while varying, all but one enzyme tolerate the corresponding mthN/mthNTP substrates. The robust emission quantum yields, high photophysical responsiveness and enzymatic accommodation suggest that the mthN alphabet is a biophysically viable tool and can be used to probe the tolerance of nucleoside/tide-processing enzymes to structural perturbations of their substrates. 相似文献
10.
Dr. Virginia Valderrey Dr. Kornelia Gawlitza Dr. Knut Rurack 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(21):e202104525
Bifunctional fluorescent molecular oxoanion probes based on the benzoxadiazole (BD) chromophore are described which integrate a thiourea binding motif and a polymerizable 2-aminoethyl methacrylate unit in the 4,7-positions of the BD core. Concerted charge transfer in this electron donor-acceptor-donor architecture endows the dyes with strongly Stokes shifted (up to >250 nm) absorption and fluorescence. Binding of electron-rich carboxylate guests at the thiourea receptor leads to further analyte-induced red-shifts of the emission, shifting the fluorescence maximum of the complexes to ≥700 nm. Association constants for acetate are ranging from 1–5×105 M−1 in acetonitrile. Integration of one of the fluorescent probes through its polymerizable moiety into molecularly imprinted polymers (MIPs) grafted from the surface of submicron silica cores yielded fluorescent MIP-coated particle probes for the selective detection of antibiotics containing aliphatic carboxylate groups such as enoxacin (ENOX) at micromolar concentrations in highly polar solvents like acetonitrile. 相似文献