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921.
Jun Pan Yuchen Zhang Fu Sun Markus Osenberg André Hilger Ingo Manke Ruiguo Cao Shi Xue Dou Hong Jin Fan 《Angewandte Chemie (International ed. in English)》2023,62(17):e202219000
Unstable cathode-electrolyte and/or anode-electrolyte interface in polymer-based sodium-ion batteries (SIBs) will deteriorate their cycle performance. Herein, a unique solvated double-layer quasi-solid polymer electrolyte (SDL-QSPE) with high Na+ ion conductivity is designed to simultaneously improve stability on both cathode and anode sides. Different functional fillers are solvated with plasticizers to improve Na+ conductivity and thermal stability. The SDL-QSPE is laminated by cathode- and anode-facing polymer electrolyte to meet the independent interfacial requirements of the two electrodes. The interfacial evolution is elucidated by theoretical calculations and 3D X-ray microtomography analysis. The Na0.67Mn2/3Ni1/3O2|SDL-QSPE|Na batteries exhibit 80.4 mAh g−1 after 400 cycles at 1 C with the Coulombic efficiency close to 100 %, which significantly outperforms those batteries using the monolayer-structured QSPE. 相似文献
922.
碳酸二甲酯(DMC)是一种重要的工业产品, 被广泛应用于制备锂离子电池溶剂和聚碳酸酯等化工产品. 一氧化碳(CO)酯化反应制DMC是一种新型的碳一技术路线, 具有成本低、反应效率高和安全等优势, 近年来引起了广泛的研究兴趣. 许多研究表明, Pd单位点催化剂(Pd SSCs)可以催化该反应高选择性合成DMC, 却易被反应物CO还原成Pd纳米颗粒, 从而导致DMC选择性快速下降. 因此, 设计合成稳定的Pd SSCs显得尤为重要. 通常, 研究人员通过增加Pd原子与载体之间的相互作用来稳定催化剂. 在各种载体中, 金属有机框架材料(MOFs)由于具有比表面积大、稳定性好、可修饰性强等特点, 是稳定单金属位点的理想载体. 选择自身较为稳定且易修饰的UiO-66-NH2作为载体, 采用后合成修饰的方法将吡啶-2-甲醛引入UiO-66-NH2的孔中. 吡啶-2-甲醛通过与氨基进行反应连接在UiO-66-NH2的框架上, 进而创造了相近的双氮原子位点共同鳌合Pd原子, 记为PdII-UiO-66-X%. 该催化剂在反应中, 展现出极高的DMC选择性, 同时也具备良好的催化稳定性, 在70 h的连续评价中, 依旧能够保持85%以上的DMC选择性. 该工作这一发现对构筑稳定Pd SSCs高选择性催化合成DMC提供了新思路. 相似文献
923.
《Arabian Journal of Chemistry》2022,15(2):103603
Heterogeneous catalysts, named SPS (sodium potassium silicates), were synthesized with an alternative silica (MPI silica) obtained from beach sand. In this work, the MPI was modified with NaOH and KOH producing silicate-based catalyst for biodiesel synthesis from waste cooking oil (WCO). The obtained catalyst was characterized by XRD, CO2-TPD, the Hammett basicity test, XRF, FESEM, EDX, FTIR and TG/DTG. The results confirmed the presence of K2O/Na2O oxides and their silicates, the main active sites responsible for the catalytic action. CO2-TPD and the Hammett basicity data suggested the presence of weak, medium and strong basic sites. Biodiesel yield was about 92% and the SPS catalyst was reused for five cycles. The biodiesel conversion by NMR 1H was about 93.89%. The DTG deconvolution revealed the decomposition of four typical biodiesel compounds (R2 = 0.9987). The method applied for the WCO biodiesel production using SPS catalyst represents an environmentally friendly process, based on low-cost material and reuse of waste biomass. 相似文献
924.
Sodium/taurocholate cotransporting polypeptideNTCPSLC10A1mediates the entry of hepatitis B virusHBVinto hepatocytes. NTCP is the functional receptor for HBV infection and a potential target for anti-HBV drugs. At presentmethods that evaluate the interaction between NTCP and its ligands are still limited. In this paperthe recombinant NTCP was expressed by Sf9 cells and purifiedand fixed on the surface plasmon resonanceSPRsensor chip by indirect antibody coupling. According to SPR kinetic analysisthe equilibrium dissociation constant KD of HBV PreS1 polypeptide binding to NTCP is 4.93 μµmol/L. The equilibrium dissociation constant KD of classic substrate taurocholate sodium for NTCP is 25.3 μµmol/L. Rather than the inhibition capacity of compounds to block NTCP substrate transportationthe equilibrium dissociation constant measured by SPR method can compare the binding affinity of compounds to NTCPand can be used to develop anti-HBV drugs based on NTCP-PreS1 interaction. © 2022, Youke Publishing Co.,Ltd. All rights reserved. 相似文献
925.
A method is described for the activation of Sepharose withN,N′-disuccimidyl carbonate. The activated carbonate reacts smoothly with amine-containing ligands yielding stable carbamate derivatives. 相似文献
926.
Separation and simultaneous determination of four artificial sweeteners in food and beverages by ion chromatography 总被引:7,自引:0,他引:7
In this paper, the separation and determination of four artificial sweeteners (aspartame, sodium cyclamate, acesulfame-K and sodium saccharin) by ion chromatography coupled with suppressed conductivity detector is reported. The four artificial sweeteners were separated using KOH eluent generator. Due to the use of eluent generator, very low conductance background conductivity can be obtained and sensitivity of sweeteners has been greatly improved. Under the experimental condition, several inorganic anions, such as F-, Cl-, NO3-, NO2-, Br-, SO4(2)-, PO4(3)- and some organic acid such as formate, acetate, benzoate, and citrate did not interfere with the determination. With this method, good linear relationship, sensitivity and reproducibility were obtained. Detection limits of aspartame, sodium cyclamate, acesulfame-K, sodium saccharin were 0.87, 0.032, 0.019, 0.045 mg/L, respectively. Rate of recovery were between 98.23 and 105.42%, 99.48 and 103.57%, 97.96 and 103.23%, 98.46 and 102.40%, respectively. The method has successfully applied to the determination of the four sweeteners in drinks and preserved fruits. 相似文献
927.
928.
磷酸锆类层柱催化剂的制备、表征及其催化甲醇氧化羰基化反应性能 总被引:9,自引:0,他引:9
以层状α-磷酸锆为插层主体,采用高温固相离子交换插层法制备Cu^2+,K柱撑的磷酸锆类层柱催化剂,并用XRD,IR和TG等方法对其进行了表征。结果表明,金属离子柱撑的α-磷酸锆类层柱催化剂的层间距由原来的0.76nm扩撑至0.81nm,结晶度有所下降。 相似文献
929.
用浸渍法制备了BaCO3-Pt/γ-Al2O3 和Pt-BaCO3/γ-Al2O3 两种样品. X射线衍射和显微红外等表征结果表明, BaCO3可以在载体表面实现单层分散; Pt和BaCO3的负载顺序不同,则BaCO3的分散容量不同. 以1%Pt/γ-Al2O3 为载体制备的 BaCO3-Pt/γ-Al2O3 样品中BaCO3的分散阈值为0.24 g/g. 氮氧化物存储量测试结果表明, BaCO3负载量在分散阈值时, NOx的吸附穿透时间和钡离子的有效利用率均达到最大值,表现出阈值效应. 而在BaCO3/γ-Al2O3 上负载Pt制备的1%Pt-BaCO3/γ-Al2O3 样品中, BaCO3的分散容量降低, 氮氧化物存储量也降低. 分散相的BaCO3在氮氧化合物存储过程中起主要作用,选择钡含量在分散阈值附近并采取先负载Pt后负载BaCO3的制样顺序可以得到吸附能力最强和钡离子有效利用率最高的催化剂. 相似文献
930.
Na4Br(NH2)3: An Amide Bromide in the System NaNH2/NaBr The pseudobinary system NaNH2/NaBr was investigated by X-ray methods. The crystal structure of Na4Br(NH2)3 was solved by single crystal data: Pnnm, Z = 4, a = 6.579(2) Å, b = 12.755(4) Å, c = 8.776(2) Å Z(Fo) with (Fo)2 ≥ 3σ = (Fo)2 = 503, Z(parameter) = 39, R/Rw = 0.082/0.106. It is a new type of structure, built up by a three-dimensional network of [Na4(NH2)3+] containing the bromide ions. 相似文献