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Nickle–Iron Layered Double Hydroxide for Enhanced Photocatalytic NO Oxidation with Significant Alleviation of NO2

Xiaoyu Li,Xiaoshu Lv,Jian Pan,Peng Chen,Huihui Peng,Yan Jiang,Haifeng Gong,Guangming Jiang,Li'an Hou,

《工程（英文）》 doi: 10.1016/j.eng.2023.06.017

摘要： Photocatalysis offers a sustainable avenue for the oxidative removal of low concentrations of NOx from the atmosphere. Layered double hydroxides (LDHs) are promising candidate photocatalysts owing to their unique layered and tunable chemical structures, and the abundant hydroxide (OH−) moieties on their surfaces that are hydroxyl radical (•OH) precursors. However, inferior charge separation and limited active sites on an LDH hinder its practical applications. Herein, we developed a facile N2H4-driven etching (et) approach that introduces dual Ni2+ and OH− vacancies (Niv and OHv) into NiFe-LDH nanosheets (referred to as NiFe-LDH-et) that facilitate improved charge-carrier separation and the formation of active Lewis acidic sites (Fe3+ and Ni2+ exposed at OHv). In contrast to inert pristine LDH, NiFe-LDH-et actively removes NO when illuminated with visible light. Specifically, Ni76Fe24-LDH-et etched in 1.50 mmol·L−1 N2H4 solution removes 32.8% of the NO from continuously flowing air (NO-feed concentration: ∼500 parts per billion (ppb)) when illuminated with visible light, thereby outperforming most reported catalysts. Experimental and theoretical data reveal that the dual vacancies promote the production of reactive oxygen species (•O2− and •OH) and the adsorption of NO on the LDH. In-situ spectroscopy revealed that NO is preferentially adsorbed at Lewis acidic sites, particularly exposed Fe3+ sites, and then converted into NO+ that is subsequently oxidized to NO3− without the formation of any of the more toxic NO2 intermediate, thereby alleviating risks associated with its production and emission.

关键词： Vacancies     Layered double hydroxide     NO     +     Photocatalysis     NO removal    

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A density functional theory study of the adsorption of Hg and HgCl2 on a CaO(001) surface

GUO Xin, ZHENG Chuguang, LU Nanxia

《能源前沿（英文）》 2007年 第1卷 第1期   页码 101-104 doi: 10.1007/s11708-007-0011-0

摘要： The adsorption of mercury and mercury chloride on a CaO(001) surface was investigated by the density functional theory (DFT) by using CaO cluster embedded in an electrostatic field represented by 178 point charges at the crystal CaO lattice positions. For the mercury molecular axis normal to the surface, the mercury can only coordinate to the O anion and has a very weak binding energy of 19.649 kJ/mol. When the mercury chloride molecular axis is vertical to the surface, the Cl atom coordinates to the Ca cation and has a binding energy of 23.699 kJ/mol. When the mercury chloride molecular axis is parallel to the surface, the Hg atom coordinates to the O anion and has a binding energy of 87.829 kJ/mol, which means that the parallel geometry is more stable than the vertical one. The present calculations show that CaO injection could substantially reduce gaseous mercury chloride, but have no apparent effect on the mercury, which is compatible with the available experimental results. This research will provide valuable information for optimizing and selecting a sorbent for the trace element in flue gas.

关键词： mercury chloride     mercury molecular     surface     cluster     electrostatic    

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Improving retrieval precision of NO

Jinpeng YANG

《机械工程前沿（英文）》 2009年 第4卷 第1期   页码 92-96 doi: 10.1007/s11465-009-0001-5

摘要： The NO density error retrieved by the traditional method of differential optical absorption spectroscopy (DOAS) was analyzed. The technique for reducing the error is proposed and used to obtain the NO density of Chengdu through DOAS.

关键词： absorption structure     low-frequency structure     absorption cross-section     NO2 density    

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Mechanism insight into the formation of HS from thiophene pyrolysis: A theoretical study

《环境科学与工程前沿（英文）》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1404-8

摘要：

• Possible formation pathways of H2S were revealed in thiophene pyrolysis.

关键词： Density functional theory     Waste rubber     Thiophene     H2S     Pyrolysis    

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Efficient synthesis of titania nanotubes and enhanced photoresponse of Pt decorated TiO

Yuxin YIN, Xin TAN, Feng HOU, Lin ZHAO

《化学科学与工程前沿（英文）》 2009年 第3卷 第3期   页码 298-304 doi: 10.1007/s11705-009-0019-6

摘要： We investigated the effect of HMT (hexamethylenetetraamine) on the anodic growth of TiO nanotube arrays. The tube length increases to 4.3 μm with HMT concentration increasing to 0.04 mol·L . Adsorption of HMT on the TiO surface is shown to markedly decrease the chemical dissolution rate of tube mouth, resulting in longer nanotube length. Furthermore, Pt nanoparticles were successfully deposited on the surface of TiO nanotubes by ac electrodeposition method. The TiO /Pt composites were characterized by field emission scanning electron microscope (FESEM), X-ray photoelectron spectra (XPS), and photoelectrochemistry. An enhancement in photocurrent density has been achieved upon modification of TiO nanotubes with Pt nanoparticles.

关键词： TiO2 nanotube arrays     HMT     TiO2/Pt     Photocurrent density    

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Effect of current density on groundwater arsenite removal performance using air cathode electrocoagulation

《环境科学与工程前沿（英文）》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1399-1

摘要：

• With the same charge, current density had little effect on As(III) removal in ACEC.

关键词： Electrocoagulation     Air cathode     Arsenic     Current density     Energy consumption    

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Effects of exercise therapy on bone mineral density in early postmenopausal women: a controlled trial

Shilin DENG MD ,

《医学前沿（英文）》 2009年 第3卷 第3期   页码 323-329 doi: 10.1007/s11684-009-0061-2

摘要： The purpose of this article is to determine the effect of a well-designed combined aerobic, resistance, and extension exercise program on bone mineral density (BMD) in postmenopausal women. The population comprised 45 postmenopausal women, who exercised over 12months (exercise group), and 36 women who served as a non-training control group. BMD of the hip, and lumbar spine was measured at the baseline and 12th month. Repeated measurement analysis of variance and nonparametric test were utilized to compare differences between the exercise group and controls. Thirty-six out of 45 persons in the exercise group and 36 controls completed the study. Average compliance was 82.2% for the whole exercise group at the 12th month. All the subjects had decreased BMD, but the rate of bone loss was lower in the exercise group than in the control group at the L4 and hip. Although the exercise program in this study may probably reduce the rate of bone loss in weight-bearing skeletal sites, we do not suggest the exercise by itself be viewed as prevention or treatment for osteoporosis. Further, the exact dose-response relationship of exercise and bone mass in early postmenopause is not clear.

关键词： early postmenopausal women     bone mineral density     exercise     effects    

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density measurement for plastic injection molding via ultrasonic technology

《机械工程前沿（英文）》 2022年 第17卷 第4期 doi: 10.1007/s11465-022-0714-2

摘要： Density variation during the injection molding process directly reflects the state of plastic melt and contains valuable information for process monitoring and optimization. Therefore, in-situ density measurement is of great interest and has significant application value. The existing methods, such as pressure−volume−temperature (PVT) method, have the shortages of time-delay and high cost of sensors. This study is the first to propose an in-situ density measurement method using ultrasonic technology. The analyses of the time-domain and frequency-domain signals are combined in the proposed method. The ultrasonic velocity is obtained from the time-domain signals, and the acoustic impedance is computed through a full-spectral analysis of the frequency-domain signals. Experiments with different process conditions are conducted, including different melt temperature, injection speed, material, and mold structure. Results show that the proposed method has good agreement with the PVT method. The proposed method has the advantages of in-situ measurement, non-destructive, high accuracy, low cost, and is of great application value for the injection molding industry.

关键词： ultrasonic measurement     melt density     in-situ measurement     injection molding    

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Relationship of adrenomedullin expression and microvessel density and prognosis in smooth muscle tumor

JIANG Yuan, TIAN Xuehong, YUAN Jie, JIN Yuemei, TAN Yusong

《医学前沿（英文）》 2007年 第1卷 第4期   页码 398-400 doi: 10.1007/s11684-007-0077-4

摘要： The aim of this paper was to investigate the relationship between the expression of adrenomedullin (ADM) and microvessel density (MVD) and prognosis in smooth muscle tumor of uterus. The expression of ADM was detected using immunohistochemical staining in specimens from 15 normal controls, 28 cases of uterine leiomyoma (LE) and 19 cases of uterine leiomyosarcoma (LES). The MVD was assayed by immunostainting with CD. There was a positive correlation between the ADM expression and MVD in LE and LES respectively ( = 0.823, <0.01; = 0.793, <0.01). The expression of ADM in LE was statistically lower than that in LES (<0.05). There was a positive correlation between the ADM expression and mitotic figures in LES (<0.05): the more mitotic figures, the higher levels of the ADM expression and poor prognosis. The ADM is an important angiogenic factor in smooth muscle tumor of uterus. The ADM can be used as an accessory marker in estimating the malignant potency of LE and judging the pro gnosis of LES, and as a novel molecular target of anti-angiogenic and anticarcinogenic strategies.

关键词： anticarcinogenic     microvessel density     malignant potency     muscle     uterine leiomyosarcoma    

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metastasis is related to the epithelial-mesenchymal transition and expressions of VEGF, MMP-9, and COX-2

Lihui WANG, Lianhong LI, Shen LV, Shujun FAN, Li ZHAN, Bo WANG, Zhong ZHANG

《医学前沿（英文）》 2009年 第3卷 第2期   页码 164-170 doi: 10.1007/s11684-009-0038-1

摘要： The invasion and metastasis of breast cancer are supposed to involve several stages in which epithelial-mesenchymal transition (EMT) is regarded as the mechanistic basis for the behavior of cancer cells. A series of factors related to EMT are apparently involved in such process. The current study aimed to investigate the contributions of EMT and related factors in lymph node metastasis of breast cancer. The expressions of E-cadherin (E-Cad), N-cadherin (N-Cad), vascular endothelial cell growth factor (VEGF), matrix metalloproteinase-9 (MMP-9), cyclooxygenase-2 (COX-2), and CD34 were examined in 74 cases of breast cancer, including 39 cases with lymph node metastasis and 35 cases without lymph node metastasis by immunohistochemistry. Multivariable Cox proportional hazards model was used to analyze the patients’ prognosis. The expressions of N-Cad, VEGF, MMP-9, and COX-2 in cases with lymph node metastasis were significantly higher than those without lymph node metastasis ( <0.05), while the E-Cad level was inversely related to status of lymph node metastasis ( <0.05). The metastasis rate of lymph node in the cases with EMT (lower E-Cad expression and higher N-Cad expression) was 78.3%, while that without EMT (higher E-Cad expression and lower N-Cad expression) was 11.1%. There was a statistical difference in the expression of COX-2 protein between histological grade I and grade II or III, respectively ( <0.05). In the cases with higher grade, the expression of E-Cad was decreased, while that of N-Cad was increased. Higher microvascular density (MVD) was also found to be significantly associated with lymphatic metastasis ( <0.05), and the cases with higher MVD had shorter survival time. This study indicates that EMT and expressions of VEGF, MMP-9 and COX-2, and MVD value are strongly correlated with lymph node metastasis in breast cancer.

关键词： epithelial-mesenchymal transition     vascular endothelial cell growth factor     matrix metalloproteinase-9     cyclooxygenase-2     higher microvascular density     breast cancer    

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Single-electromagnet levitation for density measurement and defect detection

Yuhan JIA, Peng ZHAO, Jun XIE, Xuechun ZHANG, Hongwei ZHOU, Jianzhong FU

《机械工程前沿（英文）》 2021年 第16卷 第1期   页码 186-195 doi: 10.1007/s11465-020-0608-0

摘要： This paper presents a single-electromagnet levitation device to measure the densities and detect the internal defects of antimagnetic materials. The experimental device has an electromagnet in its lower part and a pure iron core in the upper part. When the electromagnet is activated, samples can be levitated stably in a paramagnetic solution. Compared with traditional magnetic levitation devices, the single-electromagnet levitation device is adjustable. Different currents, electromagnet shapes, and distances between the electromagnet and iron core are used in the experiment depending on the type of samples. The magnetic field formed by the electromagnet is strong. When the concentration of the MnCl aqueous solution is 3 mol/L, the measuring range of the single-electromagnet levitation device ranges from 1.301 to 2.308 g/cm . However, with the same concentration of MnCl aqueous solution (3 mol/L), the measuring range of a magnetic levitation device built with permanent magnets is only from 1.15 to 1.50 g/cm . The single-electromagnet levitation device has a large measuring range and can realize accurate density measurement and defect detection of high-density materials, such as glass and aluminum alloy.

关键词： single-electromagnet     electromagnetic levitation     density measurement     defect detection    

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Application of gamma-ray attenuation technology in density measurement of a slurry reactor

Jian XU, Weisheng WEI, Kai ZHANG

《化学科学与工程前沿（英文）》 2010年 第4卷 第4期   页码 486-490 doi: 10.1007/s11705-010-0509-6

摘要： Axial density profile of the gas-liquid-solid mixture in a slurry bubble column was measured by gamma-ray attenuation technology. Several measures for improving measurement precision were presented based on the discussion on attenuation law. It was found that the response frequency and the ray intensity should be as high as possible to improve the measurement precision. The mass absorption coefficient depended on not the object’s thickness but the location where the object was placed between the ray source and the detector. The results showed that the density in the column decreases with the increase of column height, which indicates that the measurement by gamma-ray attenuation is reasonable.

关键词： slurry reactor     axial density distribution     gamma-ray attenuation technology    

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Gas phase ethylene polymerization over SiO

Liuzhong LI, Aiyou HAO, Ruihua CHENG, Boping LIU

《化学科学与工程前沿（英文）》 2011年 第5卷 第1期   页码 89-95 doi: 10.1007/s11705-010-0558-x

摘要： Although an important industrial catalyst for producing high density polyethylene, the SiO -supported organosilyl chromate UCC S-2 catalyst has not been fully investigated compared with the SiO -supported oxo chromium Phillips catalyst. In this work, gas phase ethylene polymerization by S-2 catalysts (Cat-1, Cat-2, and Cat-3) was carried out in a high-speed stirred-autoclave reactor. The effects of temperature, time, and pressure on kinetics, activity, and product properties were studied. All kinetics were typical built-up types with slow decay. Compared to the simple physical mixtures of Cat-1 and Cat-2, Cat-3 showed higher activity and its product had a broader molecular weight distribution, indicating new active species induced during blending of Cat-1 and Cat-2 in -hexane. The innovation by a simple catalyst technology created a new application to meet market demands.

关键词： UCC S-2 catalyst     Al-alkyl co-catalyst     gas-phase ethylene polymerization     high density polyethylene    

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Presentation of regression analysis, GP and GMDH models to predict the pedestrian density in various

Iraj BARGEGOL; Seyed Mohsen HOSSEINIAN; Vahid NAJAFI MOGHADDAM GILANI; Mohammad NIKOOKAR; Alireza OROUEI

《结构与土木工程前沿（英文）》 2022年 第16卷 第2期   页码 250-265 doi: 10.1007/s11709-021-0785-x

摘要： In this study, the relationship between space mean speed (SMS), flow rate and density of pedestrians was investigated in different pedestrian facilities, including 1 walkway, 2 sidewalks, 2 signalized crosswalks and 2 mid-block crosswalks. First, statistical analysis was performed to investigate the normality of data and correlation of variables. Regression analysis was then applied to determine the relationship between SMS, flow rate, and density of pedestrians. Finally, two prediction models of density were obtained using genetic programming (GP) and group method of data handling (GMDH) models, and k-fold and holdout cross-validation methods were used to evaluate the models. By the use of regression analysis, the mathematical relationships between variables in all facilities were calculated and plotted, and the best relationships were observed in flow rate-density diagrams. Results also indicated that GP had a higher R2 than GMDH in the prediction of pedestrian density in terms of flow rate and SMS, suggesting that GP was better able to model SMS and pedestrian density. Moreover, the application of k-fold cross-validation method in the models led to better performances compared to the holdout cross-validation method, which shows that the prediction models using k-fold were more reliable. Finally, density relationships in all facilities were obtained in terms of SMS and flow rate.

关键词： pedestrian density     regression analysis     GP model     GMDH model    

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标题 作者 时间 类型 操作

Nickle–Iron Layered Double Hydroxide for Enhanced Photocatalytic NO Oxidation with Significant Alleviation of NO2

Xiaoyu Li,Xiaoshu Lv,Jian Pan,Peng Chen,Huihui Peng,Yan Jiang,Haifeng Gong,Guangming Jiang,Li'an Hou,

期刊论文

A density functional theory study of the adsorption of Hg and HgCl2 on a CaO(001) surface

GUO Xin, ZHENG Chuguang, LU Nanxia

期刊论文

Improving retrieval precision of NO

Jinpeng YANG

期刊论文

Mechanism insight into the formation of HS from thiophene pyrolysis: A theoretical study

期刊论文

Efficient synthesis of titania nanotubes and enhanced photoresponse of Pt decorated TiO

Yuxin YIN, Xin TAN, Feng HOU, Lin ZHAO

期刊论文

Effect of current density on groundwater arsenite removal performance using air cathode electrocoagulation

期刊论文

Effects of exercise therapy on bone mineral density in early postmenopausal women: a controlled trial

Shilin DENG MD ,

期刊论文

侯阳：纳米碳基电极的结构设计与工业级电流密度下催化还原CO2机理（2021年5月21日）

2021年11月22日

会议视频

density measurement for plastic injection molding via ultrasonic technology

期刊论文

Relationship of adrenomedullin expression and microvessel density and prognosis in smooth muscle tumor

JIANG Yuan, TIAN Xuehong, YUAN Jie, JIN Yuemei, TAN Yusong

期刊论文

metastasis is related to the epithelial-mesenchymal transition and expressions of VEGF, MMP-9, and COX-2

Lihui WANG, Lianhong LI, Shen LV, Shujun FAN, Li ZHAN, Bo WANG, Zhong ZHANG

期刊论文

Single-electromagnet levitation for density measurement and defect detection

Yuhan JIA, Peng ZHAO, Jun XIE, Xuechun ZHANG, Hongwei ZHOU, Jianzhong FU

期刊论文

Application of gamma-ray attenuation technology in density measurement of a slurry reactor

Jian XU, Weisheng WEI, Kai ZHANG

期刊论文

Gas phase ethylene polymerization over SiO

Liuzhong LI, Aiyou HAO, Ruihua CHENG, Boping LIU

期刊论文

Presentation of regression analysis, GP and GMDH models to predict the pedestrian density in various

Iraj BARGEGOL; Seyed Mohsen HOSSEINIAN; Vahid NAJAFI MOGHADDAM GILANI; Mohammad NIKOOKAR; Alireza OROUEI

期刊论文