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131.
Rate constants for the gas-phase reactions of O3 with the sesquiterpenes α-cedrene, α-copaene, β-caryophyllene, α-humulene, and longifolene, and with the monoterpenes limonene, terpinolene, α-phellandrene, and α-terpinene, have been measured using a relative rate technique at 296 ± 2 K and atmospheric pressure of air. The rate constants obtained (in units of 10?17 cm3 molecule?1 s?1) are: limonene, 20.1 ± 5.1; terpinolene, 188 ± 67; α-phellandrene, 298 ± 105; α-terpinene, 2110 ± 770; α-cedrene, 2.78 ± 0.71; α-copaene, 15.8 ± 5.6; β-caryophyllene, 1160 ± 430; α-humulene, 1170 ± 450; and longifolene, <0.07, where the indicated errors include the estimated overall uncertainties in the rate constants for the reference organics. Hydroxyl radical formation yields were also determined for the O3 reactions with the sesquiterpenes, of 0.67 for α-cedrene, 0.35 for α-copaene, 0.06 for β-caryophyllene, and 0.22 for α-humulene, all with estimated overall uncertainties of a factor of ca. 1.5. The tropospheric lifetimes of the sesquiterpenes due to reaction with O3 are calculated. © 1994 John Wiley & Sons, Inc. 相似文献
132.
By using comparison theorem and constructing suitable Lyapunov functional, we study the following almost periodic nonlinear N-species competitive Lotka-Volterra model:
133.
A new polytungstoarsenate-based 3d-4f heterometallic aggregate has been synthesized, consisting of three {alpha-AsW10 O 38} fragments bridged by three {Fe-(mu3-O)3-Ce} heterometallic clusters. 相似文献
134.
135.
Shangyu Chen Yonghui Pan Kai Chen Pengfei Chen Qingming Shen Pengfei Sun Wenbo Hu Quli Fan 《Angewandte Chemie (International ed. in English)》2023,62(6):e202215372
Developing conjugated small molecules (CSM) with intense NIR-II (1000–1700 nm) absorption for phototheranostic is highly desirable but remains a tremendous challenge due to a lack of reliable design guidelines. This study reports a high-performance NIR-II CSM for phototheranostic by tailoring molecular planarity. A series of CSM show bathochromic absorption extended to the NIR-II region upon the increasing thiophene number, but an excessive number of thiophene results in decreased NIR-IIa (1300–1400 nm) brightness and photothermal effects. Further introduction of terminal nonconjugated alkyl chain can enhance NIR-II absorption coefficient, NIR-IIa brightness, and photothermal effects. Mechanism studies ascribe this overall enhancement to molecular planarity stemming from the collective contribution of donor/side-chain engineering. This finding directs the design of NIR-II CSM by rational manipulating molecular planarity to perform 1064 nm mediated phototheranostic at high efficiency. 相似文献
136.
Yonghui Qin Jingliang Li Heping Ma 《Numerical Methods for Partial Differential Equations》2016,32(6):1689-1703
The Legendre Galerkin Chebyshev collocation least squares method is presented for a second‐order elliptic problem with variable coefficients. By introducing a flux variable, the original problem is rewritten as an equivalent first‐order system. The present method is based on the Legendre Galerkin method, but Chebyshev–Gauss–Lobatto collocation is used to deal with the variable coefficient and the right hand side terms. The coercivity and continuity of the method are proved and an error estimate in the ‐norm is derived. Some numerical examples are given to validate the efficiency and accuracy of the scheme. © 2016Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 32: 1689–1703, 2016 相似文献
137.
Non‐chlorinated solvents are highly preferable for organic electronic processing due to their environmentally friendly characteristics. Four different halogen‐free solvents, tetrafuran, toluene, meta‐xylene and 1,2,4‐trimethylbenzene, were selected to fabricate n‐channel organic thin film transistors (OTFTs) based on 3‐hexylundecyl substituted naphthalene diimides fused with (1,3‐dithiol‐2‐ylidene)malononitrile groups (NDI3HU‐DTYM2). The OTFTs based on NDI3HU‐DTYM2 showed electron mobility of up to 1.37 cm2·V?1·s?1 under ambient condition. This is among the highest device performance for n‐channel OTFTs processed from halogen‐free solvents. The different thin‐film morphologies, from featureless low crystalline morphology to well‐aligned nanofibres, have a great effect on the device performance. These results might shed some light on solvent selection and the resulting solution process for organic electronic devices. 相似文献
138.
139.
Yonghui Liu Mingjing Li Haomiao Zhu Zhe Jing Xiaona Yin Kun Wang Zhangyong Hong Wei Zhao 《中国化学快报》2021,32(6):1963-1966
We have developed a MUC1 antigen-based antitumor vaccine loaded on alum colloid encapsulated insideβ-glucan particles(GP-Al). The constructed vaccine induced strong MUC1 antigen specific Ig G antibody titers and enhanced CD8~+ T cells cytotoxic effect to kill tumor cells. These results indicated that GP-Al can be served as an efficient delivery system and adjuvant for the development of cancer vaccines especially small molecule antigens based cancer vaccines. 相似文献
140.
Mengli Lei Xinran Zhou Yidong Zou Junhao Ma Fahad A. Alharthi Abdulaziz Alghamdi Xuanyu Yang Yonghui Deng 《中国化学快报》2021,32(6):1998-2004
The rapid development of internet and internet of things brings new opportunities for the expansion of intelligent sensors,and acetone as a major disease detection indicator(i.e.,diabetes) making it become extremely important clinical indicator.Herein,uniform mesoporous ZnO spheres were successfully synthesized via novel formaldehyde-assisted metal-ligand crosslinking strategy.In order to adjust the pore structure of mesoporous ZnO,various mesoporous ZnO spheres were synthesized by changing weight percentage of Zn(NO_3)_2·6 H_2 O to tannic acid(TA).Moreover,highly active heterojunction mesoporous ZnO/Co_3 O_4 has been fabricated based on as-prepared ultra-small Co_3 O_4 nanocrystals(ca.3 nm) and mesoporous ZnO spheres by flexible impregnation technique.Profit from nano-size effect and synergistic effect of p-n heterojunction,mesoporous ZnO/Co_3 O_4 exhibited excellent acetone sensing performance with high selectivity,superior sensitivity and responsiveness.Typically,5 wt% Co_3 O_4 embedded mesoporous ZnO sphere showed prominent acetone response(ca.46 for 50 ppm),which was about 11.5 times higher than that in pure ZnO sensing device,and it was also endowed high cyclic stability.The nanocrystals embedded hybrid material is expected to be used as promising efficient material in the field of catalysis and gas sensing. 相似文献