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A self-assembled monolayer (SAM) of a novel cobalt(II)porphyrin disulphide derivative was prepared on flat gold(1 1 1) electrode. Evidence for surface modification was provided by electrochemical reductive desorption of the monolayer and ellipsometry, consistent with a coverage of 2.5 × 10−10 mol cm−2 and a thickness of 13 Å, respectively. Both results support the presence of SAMs where the molecules share an intermediate position between perpendicular and flat orientation. Scanning tunnelling microscopy have also proven the formation of CoPSS SAMs, however high-resolution images could only be obtained when the CoPSS molecules were diluted in an hexanethiol SAM. The electrocatalytic activity of the surface confined Co-porphyrin was evaluated for the oxygen reduction. Voltammetric data indicate that reaction involves two electrons consistent with the formation of hydrogen peroxide. Under similar experimental conditions the data obtained for an iron-porphyrin analogue points for a full reduction of dioxygen to water. 相似文献
3.
Fengyang Wang Xueying Huang Li Du Weiguo Li Hongxuan He Chao Qi 《International journal of molecular sciences》2007,8(5):445-454
The small molecule, meso-tetra(α,α,α,α-o-phenylacetamidophenyl) porphyrin (Mr1147.0) was used as complete antigen to elicit MAb through the immunization and cell fusion techniques. The MAb 1F2 obtained was demonstrated to be very pure by MALDI/TOFMS. The subtype of MAb 1F2 is IgG2a, which has a relative molecular weight of 156,678.8 Da.No significant change in the intensity of absorption peaks in UV and CD spectra was observed over a pH range between 6 and 12. The high stability of the abzyme and the tight binding between Fe porphyrin and antibody were also demonstrated. Vmax, Km, κcat, κcat/Km for abzyme are 5.18 × 10−8 Ms−1, 1.50 × 10−8 M, 0.518 s−1, 3.45 × 107 M−1s−1, respectively. The data obtained indicate that catalytic antibody has high catalytic activity. The chloroperoxidase activity of MAb 1F2-Fe porphyrin complex is stable from 10 °C to 60 °C. 相似文献
4.
卟啉类化合物的结构特征使其在很多领域受到广泛的关注,现在通常在卟啉上做修饰以获得更优的性能。以氨基苯基取代的卟啉化合物作为二胺单体和均苯四甲酸二酐为二酐单体,以苯甲酸为溶剂,通过反应合成粗产品新型的聚酰亚胺材料,用丙酮和氯仿洗涤得到纯产品,并进一步合成了Zn-卟啉聚酰亚胺。采用傅里叶红外吸收光谱、紫外-可见吸收光谱对产物进行了结构表征,对主要的紫外光谱、红外光谱吸收带进行了经验归属,以及原料与产物的对比分析,初步确定了合成产物的结构。结果表明,聚合产物是以卟啉骨架结构为主要聚合单元的聚酰亚胺类共聚物。 相似文献
5.
以单羟基苯基钴卟啉与三聚氯氰为原料,通过亲核取代反应合成了钴卟啉的三嗪类化合物,以硅胶为固定相,二氯甲烷为洗脱剂采用柱层析的方法对产物进行分离和提纯。最后采用紫外可见光谱、红外光谱等手段对合成产物进行了结构表征,对主要的紫外光谱、红外光谱吸收带进行了经验归属,初步确定了合成产物的结构。 相似文献
6.
本文继续深入研究该体系中相关物质的红外光谱和拉曼光谱的性质.论文结果说明,在碱体系中,NaOH只与羟基苯基卟啉周边meso-位的羟基反应形成盐,这个性质与紫外可见光谱性质是一致的.同时这一结果也为研究卟啉与金属的相互作用提供了有益的理论支持. 相似文献
7.
为筛选催化环己烷氧化合成己二酸用仿生催化剂,研究了以吡咯、3,4 二甲基苯甲醛和金属盐为原料,合成一种带多个疏水性短碳链对称卟啉化合物meso-四(3,4 二甲苯基)卟啉(简称TDMPP)金属钴(Ⅱ)、铜(Ⅱ)配合物的方法,探讨了溶剂配比、反应时间、反应物的物质量浓度等对产率的影响;并利用UV Vis和IR对合成的物质结构进行了表征.结果表明合成TDMPPCo的适宜工艺参数为:v(丙酸)∶v(冰乙酸)等于2∶1;n(吡咯)∶n(3,4 甲基苯甲醛)∶n(醋酸钴)等于100∶104∶029;吡咯的物质量浓度为0.25mol/L;反应时间为50min;反应温度为125~130℃;产率达32%.合成TDMPPCu的适宜工艺参数为:v(丙酸)∶v(冰乙酸)等于3∶1,n(吡咯)∶n(3,4 甲基苯甲醛)∶n(醋酸铜)等于100∶104∶027;吡咯的物质量浓度为0.25mol/L,反应时间为50min,反应温度为130~135℃,产率达38%. 相似文献
8.
Under water-rich conditions, small amphiphilic and hydrophobic drug molecules self-assemble into supramolecular nanostructures. Thus, substantial modifications in their interaction with cellular structures and the ability to reach intracellular targets could happen. Additionally, drug aggregates could be more toxic than the non-aggregated counterparts, or vice versa. Moreover, since self-aggregation reduces the number of effective “monomeric” molecules that interact with the target, the drug potency could be underestimated. In other cases, the activity could be ascribed to the non-aggregated molecule while it stems from its aggregates. Thus, drug self-assembly could mislead from drug throughput screening assays to advanced preclinical and clinical trials. Finally, aggregates could serve as crystallization nuclei. The impact that this phenomenon has on the biological performance of active compounds, the inconsistent and often controversial nature of the published data and the need for recommendations/guidelines as preamble of more harmonized research protocols to characterize drug self-aggregation were main motivations for this review. First, the key molecular and environmental parameters governing drug self-aggregation, the main drug families for which this phenomenon and the methods used for its characterization are described. Then, promising nanotechnology platforms investigated to prevent/control it towards a more efficient drug development process are briefly discussed. 相似文献
9.
Ultrathin 2D Zirconium Metal–Organic Framework Nanosheets: Preparation and Application in Photocatalysis 下载免费PDF全文
Ting He Bing Ni Simin Zhang Yue Gong Haiqing Wang Lin Gu Jing Zhuang Wenping Hu Xun Wang 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(16)
Synthesizing ultrathin 2D metal–organic framework nanosheets in high yields has received increasing research interest but remains a great challenge. In this work, ultrathin zirconium‐porphyrinic metal–organic framework (MOF) nanosheets with thickness down to ≈1.5 nm are synthesized through a pseudoassembly–disassembly strategy. Owing to the their unique properties originating from their ultrathin thickness and highly exposed active sites, the as‐prepared ultrathin nanosheets exhibit far superior photocatalysis performance compared to the corresponding bulk MOF. This work highlights new opportunities in designing ultrathin MOF nanosheets and paves the way to expand the potential applications of MOFs. 相似文献
10.