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151.
152.
以苯磺酰肼和1-芘甲醛为原料,设计合成了一种结构简单的可快速识别汞(Ⅱ)离子(Hg2+)的磺酰腙型荧光探针(Z)-N’-(芘-1-基亚甲基)苯磺酰腙(BSB),并通过氢核磁共振波谱仪(1H NMR)对其结构进行了表征。BSB对Hg2+展示出高选择性、专一性和快速响应性,检测限为2.07×10-7mol/L,响应时间仅需15 s。通过job’s曲线,1H NMR滴定实验和高分辨率质谱(HRMS)对响应机理进行了探究,并且BSB可以检测不同水样中的Hg2+。有趣的是,将BSB和聚丙烯酰胺(PAM)相掺杂制备出了对Hg2+具有高去除性能的新型高分子材料(PAM-BSB),去除率达到99.63%,并通过扫描电子显微镜(SEM)对PAM-BSB吸附前后的微观形貌进行了观察。 相似文献
153.
提出了一种基于电光调制光学频率梳的光谱干涉测距方法.理论分析了电光调制光学频率梳的数学模型和光谱扩展原理,并分析得出了光谱干涉测距方法的非模糊范围和分辨力的影响因素.在实验中,使用三只级联的电光相位调制器调制单频连续波激光生成了40多阶高功率梳齿状边带,并通过单模光纤和高非线性光纤对电光调制器输出的激光进行光谱扩展,得到重复频率为10 GHz,光谱宽度达30 nm的光学频率梳.将该光频梳作为光谱干涉测距装置的光源,可以实现无"死区"的绝对距离测量.另外,使用等频率间隔重采样和二次方程脉冲峰值拟合算法对测量结果进行数据处理,可以修正系统误差,提升测距精度.实验结果表明,在1 m的测量范围内,使用该装置可以在任意位置达到±15μm以内的绝对测距精度. 相似文献
154.
合成了一种含苯并噻唑结构配体的环金属化铱配合物(ffbi)2Ir(acac),(其中ffbi为1-(4-氟苄基)-2-(4-氟苯基)苯并咪唑,acac为乙酰丙酮),并以其作为发光体, 制备了有机电致发光器件。结果表明该配合物具有强磷光发光特性,器件发绿色光。其中结构为TCTA(40 nm)/CBP∶Ir(6.3%,30 nm)/BCP(10 nm)/Alq(40 nm)的电致发光器件在12 V电压下最大发光亮度达41 499 cd·m-2,在8 V电压下,最大外量子效率达5.7%。 相似文献
155.
Using simulated Tianqin gravitational wave data and electromagnetic wave data to study the coincidence problem and Hubble tension problem 下载免费PDF全文
In this study, we used electromagnetic wave data (H0LiCOW, \begin{document}$ H(z) $\end{document} ![]()
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, SNe) and gravitational wave data (Tianqin) to constrain the interacting dark energy (IDE) model and investigate the Hubble tension and coincidence problems. By combining these four types of data (Tianqin+H0LiCOW+SNe+\begin{document}$ H(z) $\end{document} ![]()
![]()
), we obtained the following parameter values with a confidence interval of \begin{document}$ 1\sigma $\end{document} ![]()
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: \begin{document}$ \Omega_m=0.36\pm0.18 $\end{document} ![]()
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, \begin{document}$ \omega_x=-1.29^{+0.61}_{-0.23} $\end{document} ![]()
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, \begin{document}$ \xi=3.15^{+0.36}_{-1.1} $\end{document} ![]()
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, and \begin{document}$H_0=70.04\pm $\end{document} ![]()
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\begin{document}$ 0.42~ {\rm kms}^{-1}{\rm Mpc}^{-1}$\end{document} ![]()
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. According to our results, the best value of \begin{document}$ H_0 $\end{document} ![]()
![]()
shows that the Hubble tension problem can be alleviated to some extent. In addition, the center value of \begin{document}$ \xi+3\omega_x = -0.72^{+2.19}_{-1.19}(1\sigma) $\end{document} ![]()
![]()
indicates that the coincidence problem is slightly alleviated. However, \begin{document}$ \xi+3\omega_x = 0 $\end{document} ![]()
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is still within the \begin{document}$ 1\sigma $\end{document} ![]()
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error range, which indicates that the ΛCDM model is still the model in best agreement with the observational data at present. Finally, we compared the constraint results of the electromagnetic and gravitational waves on the model parameters and found that the constraint effect of electromagnetic wave data on model parameters is better than that of simulated Tianqin gravitational wave data. 相似文献
156.
乙醇含量的精确定量检测对于环境监测、临床诊断、食品检测以及饮用酒水都至关重要。以氯化铜(CuCl2)为铜源、聚乙烯吡咯烷酮(PVP)为保护剂、2-巯基苯并噻唑(MBT)为稳定剂、抗坏血酸(AA)为还原剂,利用声化学还原法,以绿色简单、快速便捷的手段成功合成出具有橙色荧光的铜纳米团簇(PVP-Cu NCs)。利用紫外可见吸收光谱、荧光光谱、红外光谱、透射电镜和X射线光电子能谱技术研究其结构和性能,发现PVP-Cu NCs的最佳激发波长和发射波长分别为340和580 nm,其平均粒径为6.0 nm。PVP-Cu NCs可通过聚集诱导猝灭机制实现对乙醇的灵敏检测,其荧光强度与乙醇含量在体积分数5%~45%范围内呈现出良好的线性关系,且PVP-Cu NCs可制作成乙醇检测试纸,对乙醇进行可视化检测。 相似文献
157.
采用不同方法制备了铈锆复合氧化物催化剂用于催化HCl氧化反应。自发沉积策略制备的CeO2@ZrO2催化剂中,超细CeO2纳米粒子均匀的镶嵌于非晶态ZrO2中。CeO2粒子显著的“尺寸效应”使得该催化剂具有更高的Ce3+和氧空位浓度,而较高的Ce3+和氧空位浓度使得催化剂具有优异的低温氧化还原性能和储释氧能力。催化性能测试表明,CeO2@ZrO2催化剂展现出最好的催化活性(1.90 gCl2·gcat-1·h-1),同时CeO2粒子周围非晶态的ZrO2阻碍CeO2的高温烧结,提高了该催化剂的稳定性。 相似文献
158.
159.
Qi-Wen Chen Jia-Wei Wang Xia-Nan Wang Jin-Xuan Fan Xin-Hua Liu Bin Li Zi-Yi Han Prof. Dr. Si-Xue Cheng Prof. Dr. Xian-Zheng Zhang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(48):21746-21754
By leveraging the ability of Shewanella oneidensis MR-1 (S. oneidensis MR-1) to anaerobically catabolize lactate through the transfer of electrons to metal minerals for respiration, a lactate-fueled biohybrid (Bac@MnO2) was constructed by modifying manganese dioxide (MnO2) nanoflowers on the S. oneidensis MR-1 surface. The biohybrid Bac@MnO2 uses decorated MnO2 nanoflowers as electron receptor and the tumor metabolite lactate as electron donor to make a complete bacterial respiration pathway at the tumor sites, which results in the continuous catabolism of intercellular lactate. Additionally, decorated MnO2 nanoflowers can also catalyze the conversion of endogenous hydrogen peroxide (H2O2) into generate oxygen (O2), which could prevent lactate production by downregulating hypoxia-inducible factor-1α (HIF-1α) expression. As lactate plays a critical role in tumor development, the biohybrid Bac@MnO2 could significantly inhibit tumor progression by coupling bacteria respiration with tumor metabolism. 相似文献
160.
Chao-Yang Wang Xiu-Wu Zhang Jia-Wei Wang Huifen Fu Peng Wang Chong-Chen Wang 《应用有机金属化学》2020,34(6):e5637
Organic arsenic compounds in the environment are a global threat to human health. This threat has created the urgency to develop highly efficient adsorbents with both high adsorption capacity and versatile removal of different arsenic compounds. A novel 1D zinc(II) coordination polymer, formulated as Zn2(datrz)2(bpy)Cl2 ( BUC-70 ) (datrz = guanazole, bpy = 4,4′-bipyridine), was successfully synthesized through slow evaporation at room temperature. BUC-70 exhibited an excellent adsorption capacity toward p-arsanilic acid (p-ASA) and roxarsone (ROX) in water, which could be ascribed to As–O–Zn bonding interactions and strong hydrogen-bonding interactions between the organic arsenics and BUC-70 . The maximum adsorption capacities toward p-ASA and ROX were 738 and 937 mg·g−1, respectively. BUC-70 was effective in the removal of p-ASA and ROX at low concentrations (<5 mg·l−1) from the simulated p-ASA and ROX wastewater. Furthermore, the as-synthesized BUC-70 exhibited good adsorption property toward p-ASA and ROX in wastewater simulated by lake water and tap water. After adsorptive treatment using BUC-70 , the concentrations of both p-ASA and ROX were lower than the required concentrations of the drinking water standard of the World Health Organization and the surface water standard of China. Continuous-flow, fixed-bed column experiments were performed using BUC-70 loaded on cotton as packing material to explore the potential large-scale application. 相似文献