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731.
Marcel Klinksiek Sindi Baco Prof. Sébastien Leveneur Prof. Julien Legros Dr. Christoph Held 《Chemphyschem》2023,24(4):e202200729
The solvent is of prime importance in biomass conversion as it influences dissolution, reaction kinetics, catalyst activity and thermodynamic equilibrium of the reaction system. So far, activity-based models were developed to predict kinetics and equilibria, but the influence of the catalyst on kinetics has not been succesfully predicted by thermodynamic models. In this work, the thermodynamic model ePC-SAFT advanced was used to predict the activities of the reactants and of the catalyst at various conditions (temperature, reactant concentrations, γ-valerolactone GVL cosolvent addition, catalyst concentration) for the homogeneously acid-catalyzed esterification of levulinic acid (LA) with ethanol. Different kinetic models were applied, and it was found that the catalyst influence on kinetics could be predicted correctly by simultaneously solving the dissociation equilibrium of H2SO4 catalyst along the reaction coordinate and by relating reaction kinetics to proton activity. ePC-SAFT advanced model parameters were only fitted to reaction-independent phase equilibrium data. The key reaction properties were determined by applying ePC-SAFT advanced to one experimental kinetic curve for a set of temperatures, yielding the reaction enthalpy at standard state , activation energy and the intrinsic reaction rate constant k=0.011 s−1 at 323 K, which is independent of catalyst concentration. The new procedure allowed an a-priori identification of the effects of catalyst, solvent and reactant concentration on LA esterification. 相似文献
732.
Plant growth regulators are a class of physiologically active substances that could modify or regulate basic physiological processes in the plant and defense against abiotic and biotic stresses, including natural plant growth regulators and synthetic ones. Different from natural plant growth regulators with low content and high cost of extraction in plants, synthetic ones can be produced in large-scale production and widely used in agriculture for increasing and securing yield and quality of the harvested produce. However, like pesticides, the abuse of plant growth regulators will have negative impacts on human beings. Therefore, it is important to monitor plant growth regulators residues. Due to the low concentration of plant growth regulators and complex matrices of food, it is necessary to isolate and extract plant growth regulators by appropriate adsorbents in sample preparation for obtaining satisfactory results. In the last decade, several advanced materials as adsorbents have shown superiority in sample preparation. This review briefly introduces the recent application and progress of advanced materials as adsorbents in sample preparation for extraction of plant growth regulators from the complex matrix. In the end, the challenge and outlook about the extraction of plant growth regulators of these advanced adsorbents in sample preparation are presented. 相似文献
733.
734.
Deliang Wang Junyi Gong Yu Xiong Hongzhuo Wu Zheng Zhao Dong Wang Ben Zhong Tang 《Advanced functional materials》2023,33(1):2208895
Organic ultralong room-temperature phosphorescence (RTP) materials have promising applications in anti-counterfeiting. To improve the encryption level, the exploration of organic materials with tunable solid-state long persistent luminescence is in urgent need. Herein, a series of organic ultralong RTP polymeric systems are prepared by doping versatile indolocarbazole isomers into the poly(vinyl alcohol) (PVA) matrix. Notably, the doping film 11,12-ICz@PVA exhibits excellent RTP property with an ultralong lifetime of 2.04 s and a high phosphorescence quantum yield of 44.1%. Theoretical calculations reveal that this excellent RTP property can be attributed to the strong electrostatic attraction resulting from the synergistic double hydrogen-bond between the isomer 11,12-ICz and PVA matrix. More impressively, color-tunable and time-dependent long persistent luminescence is successfully achieved through efficient phosphorescence energy transfer between the indolocarbazole isomers with ultralong blue RTP emissions and commercially available fluorescent dyes with emission colors ranging from green to red doped into the PVA matrix. Besides, diversified encryption patterns are fabricated to demonstrate the promising applications of these water-soluble doping PVA systems with tunable solid-state persistent luminescence in advanced anti-counterfeiting technology. 相似文献
735.
Zhuotong Wu Shiyan Chen Jing Li Baoxiu Wang Mengtian Jin Qianqian Liang Dong Zhang Zhiliang Han Lili Deng Xiangyang Qu Huaping Wang 《Advanced functional materials》2023,33(12):2214327
Bacterial cellulose (BC) is an environmentally friendly biomaterial that is widely investigated because it possesses a unique hierarchical nanofiber network structure as well as extraordinary performance. In this review, the formation of the BC hierarchical nanofiber network structure from the perspective of biosynthesis is illustrated based on its basic chemical and crystal structure. Moreover, the design and processing of BC-based advanced materials through biosynthesis, physical, and/or chemical modification are also reviewed. The intrinsic characteristics of BC, derived from its hierarchical structure, are analyzed to understand its structure–property–application relationships. The applications of advanced BC-based materials are reviewed, such as high-strength structural materials utilizing the properties of nanofibers, energy conversion and storage, bioelectronic interfaces, environmental remediation, and thermal management applications utilizing the ion transport properties and 3D network structures of these materials. In addition, the authors also offer their opinions and potential future research directions for sustainably developing BC-based materials. 相似文献
736.
Yanan Li Jia Wei Nan Cui Jiamei Li Mengdie Xu Guoping Pan Zijian Jiang Xueru Cui Xiruo Niu Jun Li 《Advanced functional materials》2023,33(30):2301229
Recently, atomically dispersed dual-metal sites carbocatalysts (DMSCs) make a wave in the field of persulfate-based advanced oxidation processes (PS-AOPs) in light of their ≈100% atomic utilization efficiency, high density of active sites, and superior catalytic activity. This review aims to provide a state-of-the-art overview on the development of DMSCs for activating PS. Initially, the types and properties of DMSCs are summarized, as well as the role of doping different heteroatoms is discussed. Subsequently, the properties of different carbon carriers and the methods for the synthesis of DMSCs are outlined. After that, the mechanism and application of DMSCs for the activation of PS toward organic contaminants degradation are revealed. Particularly, the mechanism of nonradical pathway is described, and the necessity of coupling DMSCs-based PS-AOPs to other processes for practical water treatment is emphasized. Finally, the formidable challenges and future research directions of DMSCs are proposed. This review is expected to provide insight into the preparation of DMSCs in the field of nanomaterials and to broaden the path for their environmental applications. 相似文献
737.
738.
Jingkang Ma Mingli Wang Hong Zhang Zhoutai Shang Lin Fu Wenli Zhang Bin Song Ke Lu 《Advanced functional materials》2023,33(20):2214430
Although batteries fitted with sodium metal anodes and sulfur cathodes are attractive for their higher energy density and lower cost, the threat of polysulfide migration in organic liquid electrolytes, uncontrollable dendrites, and corresponding safety issues has locked the deployment of the battery system. Introduction of solid-state electrolytes to replace conventional liquid-based electrolytes has been considered an effective approach to address these issues and further render solid-state sodium-sulfur battery (SSSSB) systems with higher safety and improved energy density. Nevertheless, the practical applications of SSSSB are still hampered by grand challenges, such as poor interfacial contact, sluggish redox kinetics of sulfur conversion, and Na dendrites. Currently, various strategies have been proposed and utilized to negate the problems within the solid-state battery. Herein, a timely and comprehensive review of emerging strategies to promote the development of SSSSB is presented. The critical challenges that prevent the real application of the SSSSB technique are analyzed initially. Subsequently, various strategies for boosting the development of SSSSB are comprehensively summarized, containing the developing of the advanced cathode and cathode/electrolyte interface, tailoring the solid electrolyte, and designing the stable anode and anode/electrolyte interface. Finally, further perspectives on stimulating the practical application of SSSSB technology are provided. 相似文献
739.
Giedrius Balčas Mangirdas Malinauskas Maria Farsari Saulius Juodkazis 《Advanced functional materials》2023,33(39):2215230
This perspective is an overview of a recent direction in optical 3D printing, where polymerization of crosslinkable materials and nanomaterial fillers can be guided to the final structures and new composites via high temperature annealing (HTA). Defining 3D nano/micro-structures by ultrafast laser direct writing and tailoring their precursor composition with subsequent tunability of the final properties during 750–1500 °C HTA step takes place at the large surface-to-volume ratio conditions favoring efficient pyrolysis and calcination, which are required for exchange of chemical materials/gases between glass/ceramic phase and surrounding. Previously, unexplored inorganic material formation conditions in terms of fast thermal quenching, composition mixing and surface tension guided formation can be harnessed by glass making for creation of new materials endowed with preferable technical properties. An immediate application perspective for a high durability, integrated, and active 3D micro-optics is foreseen. 相似文献