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共振能量转移 1

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Diporphyrin tweezer for multichannel spectroscopic analysis of enantiomeric excess

Daniel T. Payne, Mandeep K. Chahal, Václav Březina, Whitney A. Webre, Katsuhiko Ariga, Francis D’Souza, Jan Labuta, Jonathan P. Hill

《化学科学与工程前沿(英文)》 2020年 第14卷 第1期   页码 28-40 doi: 10.1007/s11705-019-1869-1

摘要: Chiral 1,1’-binaphthyl-linked diporphyrin ‘tweezers’ ( )- /( )- and the corresponding zinc(II) complexes ( )- /( )- were prepared as chiral host molecules, and their utility for chiral analyses (especially enantiomeric excess ( ) determinations) were evaluated. Tris(1- -dodecyl)porphyrins were used for the first time as the interacting units. Host capabilities of the diporphyrin tweezers were investigated by titrations with ( , )- and ( , )-cyclohexane-1,2-diamine (CHDA). The host molecules could be used as multichannel probes of by using UV-vis, circular dichroism (CD), fluorescence emission and H nuclear magnetic resonance ( H-NMR) methods. Chiral configurations could also be differentiated using CD or H-NMR spectroscopy. All three optical techniques give good resolution of with reasonable sensitivity considering the low concentrations used (ca. 10 mol·L ). The determination of CHDA enantiomers using NMR spectroscopy is also possible because of the reasonably well separated resonances in the case of ( , )- and ( , )-CHDA. Non-metallated ( )- /( )- hosts could not be used to detect chiral information in a strongly acidic chiral guest. This work demonstrates the utility of 1,1’-binapthyl-linked chiral hosts for chiral analysis of ditopically interacting enantiomers.

关键词: porphyrin dimer     chirality     enantiomeric excess     CD     fluorescence    

Projections of heat-related excess mortality in China due to climate change, population and aging

《环境科学与工程前沿(英文)》 2023年 第17卷 第11期 doi: 10.1007/s11783-023-1732-y

摘要:

● Four scenarios were used to project heat-related excess mortality in China.

关键词: Heat-related excess mortality     LMDI     Aging     YLL     VSLY    

Numerical simulation of bituminous coal combustion in a full-scale tiny-oil ignition burner: influence of excess

Zhengqi LI, Chunlong LIU, Xiang ZHANG, Lingyan ZENG, Zhichao CHEN

《能源前沿(英文)》 2012年 第6卷 第3期   页码 296-303 doi: 10.1007/s11708-012-0191-0

摘要: The progression of ignition was numerically simulated with the aim of realizing a full-scale tiny-oil ignition burner that is identical to the burner used in an 800 MWe utility boiler. The numerical simulations were conducted for four excess air ratios, 0.56, 0.75, 0.98 and 1.14 (corresponding to primary air velocities of 17, 23, 30 and 35 m/s, respectively), which were chosen because they had been used previously in practical experiments. The numerical simulations agreed well with the experimental results, which demonstrate the suitability of the model used in the calculations. The gas temperatures were high along the center line of the burner for the four excess air ratios. The flame spread to the burner wall and the high-temperature region was enlarged in the radial direction along the primary air flow direction. The O concentrations for the four excess air ratios were 0.5%, 1.1%, 0.9% and 3.0% at the exit of the second combustion chamber. The CO peak concentration was very high with values of 7.9%, 9.9%, 11.3% and 10.6% for the four excess air ratios at the exit of the second combustion chamber.

关键词: numerical simulation     tiny-oil ignition burner     pulverized coal     temperature field    

Comparison between inhibitor and uncoupler for minimizing excess sludge production of an activated sludge

CHEN Guowei, XI Pengge, XU Deqian, YU Hanqing

《环境科学与工程前沿(英文)》 2007年 第1卷 第1期   页码 63-66 doi: 10.1007/s11783-007-0012-6

摘要: In order to study the minimization of excess sludge production, the reduction in the excess sludge production in the presence of an inhibitor and uncoupler was studied in this work. The experimental results show that such an addition could effectively reduce the production of excess sludge. With the energy uncoupling model established in this work, energy uncoupling coefficient () was used to evaluate the reduction in excess sludge production. The energy uncoupling coefficients in the presence of dinitrophenol (dNP), Zn, and Cu was 0.75, 0.46, and 0.18, respectively. The analysis demonstrated that energy spilling occurred in the presence of dNP, and that dNP was an effective uncoupler for reducing the production of excess activated sludge without affecting the microbial respiration activity.

关键词: uncoupling coefficient     Cu     minimization     presence     uncoupling    

Mechanism on minimization of excess sludge in oxic-settling-anaerobic (OSA) process

WANG Jianfang, ZHAO Qingliang, JIN Wenbiao, LIN Jikan

《环境科学与工程前沿(英文)》 2008年 第2卷 第1期   页码 36-43 doi: 10.1007/s11783-008-0001-4

摘要: The oxic-settling-anaerobic (OSA) process is a promising wastewater treatment technique for efficiently reducing sludge production and improving the stability of process operation. In this paper, the possible factors of sludge reduction such as sludge decay, uncoupled metabolism, and anaerobic oxidation with low sludge production were discussed in the OSA process. It has been confirmed that sludge decay is the decisive cause in the OSA process, accounting for 66.7% of sludge production reduction. Sludge decay includes hydrolysis and acidogenesis of dead microorganisms and particle organic carbon adsorbed in sludge floc and endogenous metabolism. By batch experiments, it has been proven that there is energetic uncoupling in the OSA system since microorganisms were exposed to alternative anaerobic and aerobic environment. It accounts for about 7.5% of sludge production reduction. Soluble chemical oxygen demand (SCOD) released from the anaerobic sludge tank in the OSA process was used as the substrate for cryptic growth. The substrate was used for anoxic denitrifying, anaerobic phosphorus release, sulfate reduction, and methane production. These anaerobic reactions in the sludge anaerobic tank have lower sludge production than in the aerobic oxidation when equivalent SCOD is consumed, which may lead to approximately 23% of sludge reduction in the OSA process. It has been concluded that multiple causes resulted in the minimization of excess sludge in the OSA system. The microbial community structure and diversity of sludge samples from the CAS (conventional activated sludge) and OSA systems were investigated by 16 SrDNA PCR-DG-DGGE (polymerase chain reaction-double gradient-denaturing gradient gel electrophoresis). DGGE profile and cluster analysis showed more abundant species in the OSA system contrasting to microbial communities in the CAS system.

Collaborative control of fine particles and ozone required in China for health benefit

《环境科学与工程前沿(英文)》 2023年 第17卷 第8期 doi: 10.1007/s11783-023-1692-2

摘要:

● Increased DAAO offsets 3/4 of the decrease of DAAP in 2013–2020.

关键词: Excess deaths     Long-term exposure     Fine particle     Ozone    

Isolation of microbe for asymmetric reduction of prochiral aromatic ketone and its reaction characters

YANG Zhonghua, WANG Yu, WANG Guanghui, ZENG Rong, YAO Shanjing

《化学科学与工程前沿(英文)》 2007年 第1卷 第4期   页码 416-420 doi: 10.1007/s11705-007-0076-7

摘要: The favorable microbes for the asymmetric reduction of prochiral aromatic ketones was isolated from soil using acetophenone as the sole carbon source, when the asymmetric reduction of acetophenone (ACP) to chiral ?-phenethyl alcohol (PEA) was chosen as the model reaction. Two microbe strains with excellent catalytic activity were obtained. They were and identified by bacteria identification. The product of the asymmetric reduction of ACP catalyzed by was mainly R-PEA and that by was mainly S-PEA. The yield and enantiomeric excesses (e.e.) could respectively reach 75% and 90% for , and 80% and 70% for , much higher than those catalyzed by baker s yeast.

关键词: excellent catalytic     prochiral aromatic     enantiomeric     -phenethyl     catalytic activity    

Solutions for a completely saturated porous elastic solid with impeded boundaries

CHEN Yunmin, LING Daosheng, ZHU Bin, CHENG Zehai

《结构与土木工程前沿(英文)》 2007年 第1卷 第3期   页码 322-328 doi: 10.1007/s11709-007-0042-y

摘要: Analytical solutions are presented for the consolidation of a semi-infinite stratum and a finite soil layer with an impeding layer located on the surface subjected to a vertical point loading. The Laplace transform and the Hankel transform are used with respect to time and the radial coordinate, respectively. Solutions of other distributed loadings, including the circular loading, can be easily obtained by integrating those of the point loading. The consolidation degree, excess pore water pressure, vertical total stress, and the shear stress of the consolidating layer are analyzed in this study. The consolidation rate decreases with the increase in the thickness of the impeding layer. Stresses of the consolidating layer vary during the consolidation due to the coupling of the excess pore water dissipation and the soil skeleton deformation. Further, the Mandel-Cryer effect is also analyzed in this study.

关键词: coupling     vertical     pressure     excess     distributed    

Experimental study of two saturated natural soils and their saturated remoulded soils under three consolidated undrained stress paths

Mingjing JIANG, Haijun HU, Jianbing PENG, Serge LEROUEIL

《结构与土木工程前沿(英文)》 2011年 第5卷 第2期   页码 225-238 doi: 10.1007/s11709-011-0108-8

摘要: In this paper, an experimental investigation is conducted to study the mechanical behavior of saturated natural loess, saturated natural filling in ground fissure and their corresponding saturated remoulded soils under three consolidated undrained triaxial stress tests, namely, conventional triaxial compression test (CTC), triaxial compression test (TC) and reduced triaxial compression test (RTC). The test results show that stress-strain relation, i.e. strain-softening or strain-hardening, is remarkably influenced by the structure, void ratio, stress path and confining pressure. Natural structure, high void ratio, TC stress path, RTC stress path and low confining pressures are favorable factors leading to strain-softening. Excess pore pressure during shearing is significantly affected by stress path. The tested soils are different from loose sand on character of strain-softening and are different from common clay on excess pore water pressure behavior. The critical states in ′– space in CTC, TC and RTC tests almost lie on one line, which indicates that the critical state is independent of the above stress paths. As for remoulded loess or remoulded filling, the critical state line (CSL) and isotropic consolidation line (ICL) in -log ′ space are almost straight, while for natural loess or natural filling, in -log ′ space there is a turning point on the CSL, which is similar to the ICL.

关键词: stress paths     static liquefaction     natural soil     remoulded soil     loess     structure     total strength indices     excess pore pressure    

化学量子能的发现鉴定和应用

曹栋兴

《中国工程科学》 2005年 第7卷 第7期   页码 90-94

摘要:

化学量子能是处在化学能与核能间的一个新层次。过能主要来自原子外层电子向低能态跃迁时放出 的能量,只有在向“能穴”共振能量转移的触发下,才有释放过能的条件。新型氢能源作为可持续发展的能源, 可以用水在线作为氢燃料源。以自然界中存在的氦-氢系统反应为例,氦离子就是这种“能穴”,已在实验室中 测到了过能,输出输人比有超过10倍的。微观上用能谱学方法测得过程中各个阶段核素变化发出的,或用激发 的方法产生的特征谱线来鉴定发生的共振能量转移,触发外层电子的量子跃迁,放出化学量子能等过程,以及 产生的新型氢化合物。过程的宏观特征表明,只要稳定优化结果,就将在合适领域中首先得到应用。

关键词: 化学量子能     分数量子能级     共振能量转移     过功率     可持续发展新型氢能源    

Start-up of PN-anammox system under low inoculation quantity and its restoration after low-loading rate shock

Guoliang Zhang, Liang Zhang, Xiaoyu Han, Shujun Zhang, Yongzhen Peng

《环境科学与工程前沿(英文)》 2021年 第15卷 第2期 doi: 10.1007/s11783-020-1324-z

摘要: Abstract • PN-A was start-up under low inoculation amount and a higher NRR was achieved. • PN-anammox system was successfully restored by aggressive sludge discharge. • Increase in granular sludge was the important factor to rapid recovery. • Enrichment of AOB and AnAOB in granular sludge favors the stable operation. Partial nitritation (PN)-anaerobic ammonium oxidation (anammox) is a promising pathway for the biological treatment of wastewater. However, the destruction of the system caused by excessive accumulation of nitrate in long-term operation remains a challenge. In this study, PN-anammox was initialized with low inoculation quantity in an air-lift reactor. The nitrogen removal rate of 0.71 kgN/(m3·d) was obtained, which was far higher than the seed sludge (0.3 kgN/(m3·d)). Thereafter, excess nitrate build-up was observed under low-loading conditions, and recovery strategies for the PN-anammox system were investigated. Experimental results suggest that increasing the nitrogen loading rate as well as the concentration of free ammonium failed to effectively suppress the nitrite oxidation bacteria (NOB) after the PN-anammox system was disrupted. Afterwards, effluent back-flow was added into the reactor to control the up-flow velocity. As a result, an aggressive discharge of sludge that promoted the synergetic growth of functional bacteria was achieved, leading to the successful restoration of the PN-anammox system. The partial nitritation and anammox activity were in balance, and an increase in nitrogen removal rate up to 1.07 kgN/(m3·d) was obtained with a nitrogen removal efficiency of 82.4% after recovery. Besides, the proportion of granular sludge (over 200 mm) increased from 33.67% to 82.82%. Ammonium oxidation bacteria (AOB) along with anammox bacteria were enriched in the granular sludge during the recovery period, which was crucial for the recovery and stable operation of the PN-anammox system.

关键词: PN-anammox     Granular sludge     Excess nitrate build-up     Recovery strategy for partial nitrification     Aggressive discharge of sludge    

标题 作者 时间 类型 操作

Diporphyrin tweezer for multichannel spectroscopic analysis of enantiomeric excess

Daniel T. Payne, Mandeep K. Chahal, Václav Březina, Whitney A. Webre, Katsuhiko Ariga, Francis D’Souza, Jan Labuta, Jonathan P. Hill

期刊论文

Projections of heat-related excess mortality in China due to climate change, population and aging

期刊论文

Numerical simulation of bituminous coal combustion in a full-scale tiny-oil ignition burner: influence of excess

Zhengqi LI, Chunlong LIU, Xiang ZHANG, Lingyan ZENG, Zhichao CHEN

期刊论文

Comparison between inhibitor and uncoupler for minimizing excess sludge production of an activated sludge

CHEN Guowei, XI Pengge, XU Deqian, YU Hanqing

期刊论文

Mechanism on minimization of excess sludge in oxic-settling-anaerobic (OSA) process

WANG Jianfang, ZHAO Qingliang, JIN Wenbiao, LIN Jikan

期刊论文

Collaborative control of fine particles and ozone required in China for health benefit

期刊论文

Isolation of microbe for asymmetric reduction of prochiral aromatic ketone and its reaction characters

YANG Zhonghua, WANG Yu, WANG Guanghui, ZENG Rong, YAO Shanjing

期刊论文

Solutions for a completely saturated porous elastic solid with impeded boundaries

CHEN Yunmin, LING Daosheng, ZHU Bin, CHENG Zehai

期刊论文

Experimental study of two saturated natural soils and their saturated remoulded soils under three consolidated undrained stress paths

Mingjing JIANG, Haijun HU, Jianbing PENG, Serge LEROUEIL

期刊论文

化学量子能的发现鉴定和应用

曹栋兴

期刊论文

Start-up of PN-anammox system under low inoculation quantity and its restoration after low-loading rate shock

Guoliang Zhang, Liang Zhang, Xiaoyu Han, Shujun Zhang, Yongzhen Peng

期刊论文