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排序方式: 共有215条查询结果,搜索用时 265 毫秒
81.
Dr. Dik‐Lung Ma Daniel Shiu‐Hin Chan Dr. Bradley Yat‐Wah Man Dr. Chung‐Hang Leung 《化学:亚洲杂志》2011,6(4):986-1003
Metal ions are prevalent in biological systems and are critically involved in essential life processes. However, excess concentrations of metals can pose a serious danger to living organisms. Oligonucleotides represent a versatile sensing platform for the detection of various molecular entities including metal ions. This review summarizes the recent advances in the development of oligonucleotide‐based luminescent detection methods for metal ions. 相似文献
82.
Shang-Yuan Shiu 《Journal of Theoretical Probability》2013,26(2):480-488
We throw i.i.d. random squares S 1,S 2,… with respective side lengths l 1,l 2,… uniformly on the two-dimensional torus ?/?×?/?, where $\{l_{n}\}_{n=1}^{\infty}$ is a nonincreasing sequence with 0<l n <1 and lim n→∞ l n =0. A necessary and sufficient condition for covering the connected curve {0}×?/? is $$\sum_{n=1}^{\infty}\frac{l_n}{(\sum_{i=1}^{n}l_i)^2}\exp{\Biggl(\sum _{i=1}^{n}l_i^2\Biggr)}=\infty.$$ 相似文献
83.
Yeu-Shiang Huang Wei-Chen ChangWei-Hao Li Zu-Liang Lin 《European Journal of Operational Research》2013
Multi-attribute utility theory (MAUT) elicits an individual decision maker’s preferences for single attributes and develops a utility function by mathematics formulation to add up the preferences of the entire set of attributes when assessing alternatives. A common aggregation method of MAUT for group decisions is the simple additive weighting (SAW) method, which does not consider the different preferential levels and preferential ranks for individual decision makers’ assessments of alternatives in a decision group, and thus seems too intuitive in achieving the consensus and commitment for group decision aggregation. In this paper, the preferential differences denoting the preference degrees among different alternatives and preferential priorities denoting the favorite ranking of the alternatives for each decision maker are both considered and aggregated to construct the utility discriminative values for assessing alternatives in a decision group. A comparative analysis is performed to compare the proposed approach to the SAW model, and a satisfaction index is used to investigate the satisfaction levels of the final two resulting group decisions. In addition, a feedback interview is conducted to understand the subjective perceptions of decision makers while examining the results obtained from these two approaches for the second practical case. Both investigation results show that the proposed approach is able to achieve a more satisfying and agreeable group decision than that of the SAW method. 相似文献
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85.
Hoi‐Yan Shiu Tak‐Chung Chan Dr. Chi‐Ming Ho Dr. Yungen Liu Dr. Man‐Kin Wong Dr. Chi‐Ming Che Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(15):3839-3850
Enriched cleavage : An efficient chemoselective cysteine modification of unprotected peptides and proteins has been developed by using electron‐deficient alkynes in aqueous media. Interestingly, terminal alkynone‐modified peptides could be converted back into the unmodified peptides by cleavage by adding thiols under mild conditions (see scheme).
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A novel experimental technique has been developed to measure the attributes of product pair correlation of bimolecular reactions under the crossed molecular beam condition. The first system that we picked is F + CD4/CHD3 / CH4 reactions. By combining a crossed molecular beam method with a time-sliced ion velocity imaging technique,the product state-resolved pair-correlated differential cross sections were revealed directly from the measurements. Several facets of the product pair correlation have been explored. The dependence on the collisional energy has been elucidated. The pair-correlated angular distributions show strong dependences on the HF/DF vibrational quantum numbers,and weaker yet not negligible dependences on the methyl radical vibrational quantum numbers. For the F + CH4 reaction at collisional energies close to the reaction threshold,the first experimental evidences of a reactive resonance in a polyatomic reaction were discovered. The product pair-correlated information helps us to unravel the complexity of polyatomic reactions and offers the important link between A + BC type of reactions and more general polyatomic reactions. 相似文献
89.
Tien-Lin Wu Jian Lei Chia-Min Hsieh Yi-Kuan Chen Pei-Yun Huang Po-Ting Lai Tsu-Yu Chou Wei-Chen Lin Wei Chen Chi-Hua Yu Liang-Yan Hsu Hao-Wu Lin Chien-Hong Cheng 《Chemical science》2022,13(44):12996
Owing to the high technology maturity of thermally activated delayed fluorescence (TADF) emitter design with a specific molecular shape, extremely high-performance organic light-emitting diodes (OLEDs) have recently been achieved via various doping techniques. Recently, undoped OLEDs have drawn immense attention because of their manufacturing cost reduction and procedure simplification. However, capable materials as host emitters are rare and precious because general fluorophores in high-concentration states suffer from serious aggregation-caused quenching (ACQ) and undergo exciton quenching. In this work, a series of diboron materials, CzDBA, iCzDBA, and tBuCzDBA, is introduced to realize the effect of steric hindrance and the molecular aspect ratio via experimental and theoretical studies. We computed transition electric dipole moment (TEDM) and molecular dynamics (MD) simulations as a proof-of-concept model to investigate the molecular stacking in neat films. It is worth noting that the pure tBuCzDBA film with a high horizontal ratio of 92% is employed to achieve a nondoped OLED with an excellent external quantum efficiency of 26.9%. In addition, we demonstrated the first ultrathin emitting layer (1 nm) TADF device, which exhibited outstanding power efficiency. This molecular design and high-performance devices show the potential of power-saving and economical fabrication for advanced OLEDs.A strategy of substituent engineering of DBA-based molecules is investigated via experimental and theoretical methods. A 1 nm-thick emitting layer OLED has been developed. 相似文献
90.
A general procedure for the synthesis of NG-alkyl, and NG-aryl-L -arginines with relatively high overall yield is reported. The key step involved the coupling of protected L -ornithine 4 with isothiourea 7 to give the fully protected NG-aryl-L -arginine derivative 8 . Subsequent deprotection of 8 in acidic condition provided the final target compound 9 with an overall yield of more than 80%. 相似文献