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971.
① YAO Lingshi 《半导体光子学与技术》1996,(4)
NewMethodofParameterIdentificationbyUsingWalshMatrix①YAOLingshi(YanshanUniversity,Qinhuangdao066004,CHN)Abstract:ByusingWalsh... 相似文献
972.
R. Kaiser 《Fresenius' Journal of Analytical Chemistry》1972,261(1):1-10
Zusammenfassung Internationale Vereinbarungen, welche teilweise bereits Gesetz wurden, und die Forderung nach Einheitlichkeit und Vergleichbarkeit analytischer Informationen machen eine Neufestlegung von bestimmten Definitionen und Bezeichnungen in der Analytik notwendig.Mengeneinheiten und Mengenbereiche (Arbeits-, Probenmengen- und Gehaltsbereiche) werden definiert und benannt, wobei ein in sich logisches und zugleich auf optimale Lösungen analytischer Probleme hinführendes System angestrebt wurde.Die Zusammenhänge zwischen den definierten Bereichen, Empfehlungen für Methodenbenennungen, das Problem von ppm- und ppb-Angaben sowie die unbrauchbare Angabe 0% als Bereichsbeginn für Meßverfahren werden diskutiert. Umrechnungsbeziehungen für Gehaltssysteme werden angegeben.Teil I: diese Z. 256, 257–270 (1971) 相似文献
973.
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976.
Gönenç Yücel Catherine Miluska Chiong Meza 《Computational & Mathematical Organization Theory》2008,14(4):320-349
The emerging need for societal transitions raises the need for a better understanding of the dynamic nature of large scale
societal systems, and therefore the development of an analytical approach for drawing dynamic conclusions based on system’s
dynamic mechanisms, feedback relationships and interacting components.
The objective of this study is to explore the degree to which System Dynamics as an approach enhances the process of understanding
transition dynamics in socio-technical systems. In other words, it is aimed to reveal the type of insights that can be developed
about such systems and their dynamic behaviour using the approach, as well as the shortcomings of the approach in this challenging
task. In order to do so, a modeling study aiming to understand the underlying mechanisms of the waste management transition
in the Netherlands is conducted.
The quantitative model developed is based on the historical case of the waste management transition of the Netherlands, and
it portrays issues as the dynamics of actors’ preferences, development of infrastructure and environmental consequences of
dominant mode of functioning and provides an instance for demonstrating and evaluating the feedback-focused perspective discussed
in this paper.
Finally, the paper discusses a set of points regarding the utilized approach, System Dynamics, observed during this study
both in general and in the specific context of transitions. In short, System Dynamics stands as a promising approach mainly
due to its strength in explaining the source of complex dynamics based on interacting feedback loops, but it also has certain
drawbacks in the context of transitions.
相似文献
Catherine Miluska Chiong MezaEmail: |
977.
Diana C. Vinueza-Espinosa Daniel R. Cuesta-Aguirre Assumpció Malgosa Cristina Santos 《Electrophoresis》2023,44(17-18):1423-1434
Poor nuclear DNA preservation from highly degraded skeletal remains is the most limiting factor for the genetic identification of individuals. Mitochondrial DNA (mtDNA) typing, and especially of the control region (CR), using next-generation sequencing (NGS), enables retrieval of valuable genetic information in forensic contexts where highly degraded human skeletal remains are the only source of genetic material. Currently, NGS commercial kits can type all mtDNA-CR in fewer steps than the conventional Sanger technique. The PowerSeq CRM Nested System kit (Promega Corporation) employs a nested multiplex-polymerase chain reaction (PCR) strategy to amplify and index all mtDNA-CR in a single reaction. Our study analyzes the success of mtDNA-CR typing of highly degraded human skeletons using the PowerSeq CRM Nested System kit. We used samples from 41 individuals from different time periods to test three protocols (M1, M2, and M3) based on modifications of PCR conditions. To analyze the detected variants, two bioinformatic procedures were compared: an in-house pipeline and the GeneMarker HTS software. The results showed that many samples were not analyzed when the standard protocol (M1) was used. In contrast, the M3 protocol, which includes 35 PCR cycles and longer denaturation and extension steps, successfully recovered the mtDNA-CR from highly degraded skeletal samples. Mixed base profiles and the percentage of damaged reads were both indicators of possible contamination and can provide better results if used together. Furthermore, our freely available in-house pipeline can provide variants concordant with the forensic software. 相似文献
978.
Yuntao Tang Yige Zhang Xi Chen Xiaowen Xie Ning Zhou Dr. Zhifeng Dai Prof. Dr. Yubing Xiong 《Angewandte Chemie (International ed. in English)》2023,62(4):e202215722
Thermally induced reversible up/down migration of poly(ionic liquid)s (PILs) in aqueous two-phase systems (ATPSs) was achieved for the first time in this study. Novel ATPSs were fabricated using azobenzene (Azo)- and benzyl (Bn)-modified PILs, and their upper and lower phases could be easily tuned using the grafting degree (GD) of the Azo and Bn groups. Bn-PIL with higher GDBn could go up into the upper phase and Azo-PIL come down to the lower phase when the temperature increased (>65 °C); this behavior was reversed at lower temperatures. Moreover, a reversible two-phase/single-phase transition was realized under UV irradiation. Experimental and simulation results revealed that the difference in the hydration capacity between Bn-PIL and Azo-PIL accounted for their unique phase-separation behavior. A versatile platform for fabricating ATPSs with tunable stimuli-responsive behavior can be realized based on our findings, which can broaden their applications in the fields of smart separation systems and functional material development. 相似文献
979.
A compact hand-held heated fluorometric instrument for performing real-time isothermal nucleic acid amplification and detection is described. The optoelectronic instrument combines a Printed Circuit Board/Micro Electro Mechanical Systems (PCB/MEMS) reaction detection/chamber containing an integrated resistive heater with attached miniature LED light source and photo-detector and a disposable glass waveguide capillary to enable a mini-fluorometer. The fluorometer is fabricated and assembled in planar geometry, rolled into a tubular format and packaged with custom control electronics to form the hand-held reactor. Positive or negative results for each reaction are displayed to the user using an LED interface. Reaction data is stored in FLASH memory for retrieval via an in-built USB connection. Operating on one disposable 3 V lithium battery >12, 60 min reactions can be performed. Maximum dimensions of the system are 150 mm (h) × 48 mm (d) × 40 mm (w), the total instrument weight (with battery) is 140 g. The system produces comparable results to laboratory instrumentation when performing a real-time nucleic acid sequence-based amplification (NASBA) reaction, and also displayed comparable precision, accuracy and resolution to laboratory-based real-time nucleic acid amplification instrumentation. A good linear response (R2 = 0.948) to fluorescein gradients ranging from 0.5 to 10 μM was also obtained from the instrument indicating that it may be utilized for other fluorometric assays. This instrument enables an inexpensive, compact approach to in-field genetic screening, providing results comparable to laboratory equipment with rapid user feedback as to the status of the reaction. 相似文献
980.
D.D. Hai 《Journal of Mathematical Analysis and Applications》2007,334(2):965-976
We prove existence and nonexistence of positive solutions for the quasilinear system