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Repairing of rutin to the toxicity of combined F-53B and chromium pollution on the biofilm formed by Pseudomonas aeruginosa

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Journal of Environmental Sciences 2023年第5期127卷 158-168页

作者： Yunhao zhang Yi qian Ming zhang Weichuan Qiao Department of Environmental Engineering College of Biology and the EnvironmentNanjing Forestry UniversityNanjing 210037China

The wastewater discharge from the process of chrome plating,which contains 6:2 chlorinated polyfluorinated ether sulfonate(F-53B)and chromium(Cr),may be toxic to *** this study we found that the biofilm formed by Pseudomonas aeruginosa PAO1 was inhibited by exposure to a combination of F-53B and Cr(VI).The combined pollution damaged the cell membranes and the structure of the biofilm,and inhibited the production of the Pseudomonas quinolone-based signal,which affected biofilm ***,the secretion of extracellular polymeric substances decreased as a result of this combined *** to F-53B and Cr(VI)individually or in combination could induce the excessive accumulation of intracellular reactive oxygen species(ROS),and the ROS positive rate of the bacteria increased under the treatment with 0.2 mmol/L of Cr(VI)and 250 nmol/L of F-53B,*** addition,the activities of superoxide dismutase(SOD)and catalase(CAT)were enhanced for scavenging ROS in the bacteria that were exposed to Cr(VI)and *** an antioxidant,rutin was used to repair the toxicity of Cr(VI)and F-53B towards the biofilm formed by the *** rutin was added to the bacteria medium,with either Cr(VI)or F-53B as pollutant,or with the combined pollutants,the extracellular protein content of the bacteria recovered to 0.84,0.94,and 0.85 times that of the control,***,the accumulation of ROS and the activities of SOD and CAT decreased,which indicated that the addition of rutin can alleviate the oxidative stress and promote the antioxidant stress system.

关键词： F-53B Chromium(Cr) Rutin Biofilm Toxic effect Repair

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Mn基低温脱硝催化剂性能优化研究进展

工程科学学报 2025年第1期47卷 142-157页

作者：许芸邬博宇庄柯张乾徐静馨张深根朱法华张柏林国家能源集团科学技术研究院有限公司低碳智能燃煤发电与超净排放全国重点实验室南京210023 北京科技大学新材料技术研究院北京100083

氮氧化物(NO_(x))是我国首要大气污染物,主要采用选择性催化还原(SCR)技术进行排放控制.研发高效、稳定的低温脱硝催化剂可避免高能耗的烟气再热,具有显著的节能降碳效益.锰氧化物(MnO_(x))因多变的化学态和丰富的晶格缺陷而表现出优良... 详细信息

氮氧化物(NO_(x))是我国首要大气污染物,主要采用选择性催化还原(SCR)技术进行排放控制.研发高效、稳定的低温脱硝催化剂可避免高能耗的烟气再热,具有显著的节能降碳效益.锰氧化物(MnO_(x))因多变的化学态和丰富的晶格缺陷而表现出优良的氧化还原性能,并具有极强的表面酸性,在催化还原NO_(x)反应中表现出良好的低温活性,但N_(2)选择性低、抗H_(2)O/SO_(2)性能差,难以实现长期的高效稳定脱硝.近年来,改性提升Mn基催化剂的研究十分广泛,加快了Mn基催化剂工业应用的步伐.本文从低温活性、N_(2)选择性和稳定性三个方面,总结了Mn基催化剂的脱硝反应机理、元素掺杂改性、催化剂结构设计等最新研究进展,指出了当前的研究重点和难点,可为下一步研究提供参考.

关键词：氮氧化物选择性催化还原锰基催化剂 N2选择性稳定性元素掺杂

An improved nonlinear onboard adaptive model for aero-engine performance control

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Chinese Journal of Aeronautics 2023年第10期36卷 317-334页

作者： qian CHEN Hanlin SHENG Tianhong zhang Jiangsu Province Key Laboratory of Aerospace Power System College of Energy and Power EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China

The onboard adaptive model can achieve the online real-time estimation of performance parameters that are difficult to measure in a real aero-engine,which is the key to realizing modelbased performance *** must possess satisfactory numerical stability and estimation ***,the positive definiteness of the state covariance matrix may be destroyed in filter estimation because of the existence of some uncertain factors,such as the accumulated measurement error,noise,and disturbance in the strongly nonlinear engine system,inevitably causing divergence of estimates of Cholesky decomposition-based Spherical Unscented Kalman Filter(SUKF).Therefore,this paper proposes an improved SUKF algorithm(iSUKF)and applies it to the performance degradation estimation of the *** to SUKF,the iSUKF mainly replaces the Cholesky decomposition with the Singular Value Decomposition(SVD),which is numerically stable without any strict requirement for the state covariance ***,a correction factor is designed to assess the measurement deviation between the real engine and the nonlinear onboard model to correct the state covariance matrix,thus maintaining better numerical stability of parameters estimated by the ***,an offline correction strategy is also proposed to eliminate the influence of the degradation of unestimated health parameters or the filter’s inadequate estimation of the coupled health *** action effectively promotes the onboard adaptive model’s estimation accuracy concerning the degradation of the engine’real health parameters and its performance ***,the simulation results show that the iSUKF can maintain the numerical stability of the filter’s estimation of health *** with the existing methods,the offline correction strategy improves the estimation accuracy of the iSUKF-based nonlinear onboard adaptive model for the performance parameters of the real engine by more than 50%.The proposed met

关键词： Aero-engine Onboard adaptive model Spherical unscented Kalman filter Parameter estimation iSUKF

Remarkable rate acceleration of SmI3-mediated iodination of acetates of Baylis-Hillman adducts in ionic liquid: facile synthesis of (Z)-allyl iodides

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第3期7卷 193-197页

作者： LIU Yun-kui ZHENG Hui XU Dan-qian XU Zhen-yuan zhang Yong-min State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology Zhejiang University of Technology Hangzhou 310014 China

Stereoselective transformation of Baylis-Hillman acetates I into corresponding （Z）-allyl iodides 2 has been achieved by treatment of I with samarium triiodide in THF. Remarkable rate acceleration of samarium triiodide-mediated iodination of 1 was found when ionic liquid 1-n-butyl-3-methyl-imidazolium tetrafluroborate （[bmim]BF4） was used as reaction media in stead of THF. This novel approach proceeds readily at 50 ℃ within a few minutes to afford （Z）-allyl iodides 2 in excellent yields. A mechanism involving stereoselective iodination of the acetates of Baylis-Hillman adducts by samarium triiodide is described, in which a six-membered ring transition state played a key role in the stereoselective formation of 2.

关键词： Baylis-Hillman adduct (Z)-allyl iodide Samarium triiodide Ionic liquid

Elucidation of Regional Mechanical Properties of Brain Tissues Based on Cell Density

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Journal of Bionic Engineering 2021年第3期18卷 611-622页

作者： Chi zhang Long qian Hongwei Zhao School of Mechanical and Aerospace Engineering Jilin UniversityChangchun 130025China

Research on the mechanical properties of brain tissue has received extensive ***,most of the current studies have been conducted at the phenomenological *** this study,the indentation method was used to explore the difference in local mechanical properties among different regions of the porcine cerebral ***,hematoxylin-eosin and immunofluorescence staining methods were used to determine the correlation between the cellular density at different test points and mechanical properties of the porcine cerebral *** frontal lobe exhibited the strongest *** temporal lobe displayed the lowest sensitivity to changes in the indentation speed,and the occipital lobe exhibited the highest shear ***,the shear modulus of different areas of the cerebral cortex was negatively correlated with the total number of local cells per unit area and positively correlated with the number of neuronal cell bodies per unit *** of the mechanical properties of the local brain tissue can provide basic data for the establishment of a finite element model of the brain and mechanical referential information for the implantation position of brain chips.

关键词： cerebral cortex mechanical properties staining correlation cellular density

Toxic effect of sodium perfluorononyloxy-benzenesulfonate on Pseudomonas stutzeri in aerobic denitrification,cell structure and gene expression

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Frontiers of Environmental Science & Engineering 2021年第5期15卷 247-256页

作者： Yi qian Weichuan Qiao Yunhao zhang Department of Environmental Engineering College of Biology and the EnvironmentNanjing Forestry UniversityNanjing210037China

The toxicities of sodium perfluorononyloxy-benzenesulfonate(OBS)to animals and plants are similar to those of perfluorooctane ***,the mechanism of its toxicity to aerobic denitrifying bacteria is still *** the present study,the ecotoxicity of OBS on an aerobic denitrifying strain,Pseudomonas stutzeri,was *** results showed that a dosage of OBS clearly affected the growth and aerobic denitrification of *** compared with an unamended control,the degradation efficiency of the total nitrogen decreased by 30.13%during exposure to 200 mg/L of OBS,and the complete degradation time of nitrate-nitrogen was delayed by 4 *** lactate dehydrogenase and superoxide dismutase produced by the bacteria increased with the concentration of OBS,and reactive oxygen species were also detected by confocal laser scanning microscope *** electron microscope imaging revealed chromosome deformation of the cells and damage to cell content;moreover,outer membrane vesicles were secreted from the bacteria,which was the important detoxification mechanism of *** to *** of the genes involved in aerobic nitrification and oxidative stress were also changed under OBS stress,which further confirmed the toxicity of OBS to P *** study reveals the environmental exposure risk of OBS from the perspective of microorganisms.

关键词： Sodium perfluorononyloxy-benzenesulfonate Aerobic denitrification Pseudomonas stutzeri Ecotoxicity ROS

Permeation of vanadium(III,IV,V)-dipicolinate complexes across MDCK cell monolayer and comparison with Caco-2 cells

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Chinese Science Bulletin 2005年第17期50卷 1854-1859页

作者： zhang Yue YANG Xiaoda WANG kui Department of Chemical Biology Laboratory of Preventive Pharmaceutics School of Pharmaceutical Science Peking University Beijing 100083 China National Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Science Peking University Beijing 100083 China

The permeation and cytotoxicity of three insu-lin-mimetic vanadium(III, IV, V)-dipicolinate complexes were studied using the MDCK cell monolayer in comparison with the Caco-2 cells. On MDCK cell monolayer, the appar-ent permeation coefficients (Papp) were estimated to be (7.5 ± 1.0)×10?6, (1.0 ± 0.2)×10?6, (1.7±0.4)×10?6 cm/s for V(V), V(IV), and V(III)-dipic complexes, respectively. The perme-ability of V(V)-dipic complexes is much better than the oth-ers, which is in agreement with its better hypoglycemic effect in animal tests. On Caco-2 cell monolayer, Papp were found to be in the range of 1-3×10?6 cm/s and not to be affected by excessive amounts of dipicolinate ligand. By contrast, the permeability in the AP→BL direction across the MDCK monolayer increased greatly in the presence of free ligands, suggesting existence of active transport mechanism of vana-dium complex anions on the MDCK cells. The cytotoxicity of the three complexes was found similar and the IC50 were measured in the range of 0.6―0.9 mmol/L for MDCK cells and 1.6―2 mmol/L for Caco-2 cells. The cytotoxicity of three vanadium complexes was conceivably in consistence with their permeability, suggesting that the toxicity, permeation and cellular metabolism of vanadium complexes are closely related.

关键词：矾化合物 MDCK 肠吸收糖尿病细胞单层

Three-dimensional coordinates test method with uncertain projectile proximity explosion position based on dynamic seven photoelectric detection screen

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Defence Technology（防务技术） 2022年第9期18卷 1643-1652页

作者： Han-shan Li Xiao-qian zhang School of Electronic and Information Engineering Xi'an Technological UniversityXi'an710021China

To objectively obtain the three-dimensional coordinates of the projectile fuze proximity explosion when projectile intersects the head of missile target, we propose a dynamic seven photoelectric detection screen test method, which is made up of six plane detection screens and a flash photoelectric dynamic detection screen. The three-dimensional coordinates calculation model of the projectile proximity explosion position based on seven plane detection screens with dynamic characteristics is *** to the relation of the dynamic seven photoelectric detection screen planes and the time values,the analytical function of the projectile proximity explosion position parameters under non-linear motion is derived. The projectile signal filtering method based on discrete wavelet transform is explored in this work. Additionally, the projectile signal recognition algorithm using an improved particle swarm is proposed. Based on the characteristics of the time duration and the signal peak error for the projectile passing through the detection screen, the signals attribution of the same projectile passing through six detection screens are analyzed for obtaining precise time values of the same projectile passing through the detection screens. On the basis of the projectile fuze proximity explosion test, the linear motion model and the proposed non-linear motion model are used to calculate and compare the same group of projectiles proximity explosion position parameters. The comparison of test results verifies that the proposed test method and calculation model in this work accurately obtain the actual projectile proximity explosion position parameters.

关键词： Dynamic multi-screen array plane Flash photoelectric detection target Projectile signal processing Particle swarm Proximity explosion fuze Three-dimensional coordinate

Icariin suppresses bone resorption activity of rabbit osteoclasts in vitro

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Chinese Science Bulletin 2007年第7期52卷 890-895页

作者： HUANG Jian zhang JinChao zhang TianLan WANG kui Department of Chemical Biology Peking University School of Pharmaceutical Sciences Beijing 100083 China Department of Chemistry College of Chemistry and Environmental Science Hebei University Baoding 071002 China Department of Chemical Biology Capital Medical University School of Pharmaceutical Sciences Beijing 100069 China

The effect of icariin on the bone resorption activity of rabbit osteoclasts is assessed in vitro. Osteoclasts were isolated from Japanese white rabbits and cultured on plates with a sterilized bone slice in each well. After treatment with icariin at various concentrations, the bone resorption activity of osteoclasts was evaluated by examining pit areas, superoxide anion (·O2-) generation, size and number of actin rings and intracellular calcium concentration [Ca2+]i. As revealed by these data, icariin elicited continuous decline of [Ca2+]i, making actin ring constricted and ·O2- generation decreased. These events resulted in smaller and fewer pits which indicate suppressed bone resorption activity of rabbit osteoclasts by icariin.

关键词：淫羊藿苷家兔破骨细胞骨骼吸收活性抑制作用