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mechanisms of diphenylarsinic acid on natural magnetite and siderite: Evidence from sorption kinetics, sequentialextraction and extended X-ray absorption fine-structure spectroscopy analysis

《环境科学与工程前沿（英文）》 2022年 第16卷 第9期 doi: 10.1007/s11783-022-1547-2

摘要：

• DPAA sorption followed pseudo-secondary and intra-particle diffusion models.

关键词： Diphenylarsinic acid (DPAA)     Sorption     Magnetite     Siderite     Sequential extraction     EXAFS    

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Field evidence of decreased extractability of copper and nickel added to soils in 6-year field experiments

Bao Jiang, Dechun Su, Xiaoqing Wang, Jifang Liu, Yibing Ma

《环境科学与工程前沿（英文）》 2018年 第12卷 第2期 doi: 10.1007/s11783-017-0990-y

摘要： The phytotoxicity of added copper (Cu) and nickel (Ni) is influenced by soil properties and field aging. However, the differences in the chemical behavior between Cu and Ni are still unclear. Therefore, this study was conducted to investigate the extractability of added Cu and Ni in 6-year field experiments, as well as the link with their phytotoxicity. The results showed that the extractability of added Cu decreased by 6.63% (5.10%–7.90%), 22.5% (20.6%–23.9%), and 6.87% (0%–17.9%) on average for acidic, neutral, and alkaline soil from 1 to 6 years, although the phytotoxicity of added Cu and Ni did not change significantly from 1 to 6 years in the long term field experiment. Because of dissolution of Cu, when the pH decreased below 7.0, the extractability of Cu in alkaline soil by EDTA at pH 4.0 could not reflect the effects of aging. For Ni, the extractability decreased by 18.1% (10.1%–33.0%), 63.0% (59.2%–68.8%), and 22.0% (12.4%–31.8%) from 1 to 6 years in acidic, neutral, and alkaline soils, respectively, indicating the effects of aging on Ni were greater than on Cu. The sum of ten sequential extractions of Cu and Ni showed that added Cu was more extractable than Ni in neutral and alkaline soil, but similar in acidic soil.

关键词： Copper     Nickel     EDTA     Sequential extraction    

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Control strategies for disinfection byproducts by ion exchange resin, nanofiltration and their sequential

《环境科学与工程前沿（英文）》 2023年 第17卷 第10期 doi: 10.1007/s11783-023-1725-x

摘要：

● Effects of AER adsorption and NF on DBP precursors, DBPs, and TOX were examined.

关键词： Disinfection byproducts     Control     Anion exchange resin     Nanofiltration     Cytotoxicity    

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Utilization of aluminum hydroxide waste generated in fluoride adsorption and coagulation processes for adsorptive removal of cadmium ion

Jiawei JU,Ruiping LIU,Zan HE,Huijuan LIU,Xiwang ZHANG,Jiuhui QU

《环境科学与工程前沿（英文）》 2016年 第10卷 第3期   页码 467-476 doi: 10.1007/s11783-015-0809-7

摘要： Although Al-based coagulation and adsorption processes have been proved highly efficient for fluoride (F) removal, the two processes both generate large amount of Al(OH) solid waste containing F (Al(OH) -F). This study aimed to investigate the feasibility of utilizing Al(OH) -F generated in Al(OH) adsorption (Al(OH) -F ) and coagulation (Al(OH) -F ) for the adsorption of cadmium ion (Cd(II)). The adsorption capacity of Al(OH) -F and Al(OH) -F for Cd(II) was similar as that of pristine aluminum hydroxide (Al(OH) ), being of 24.39 and 19.90 mg·g , respectively. The adsorption of Cd(II) onto Al(OH) -F and Al(OH) -F was identified to be dominated by ion-exchange with sodium ion (Na ) or hydrogen ion (H ), surface microprecitation, and electrostatic attraction. The maximum concentration of the leached fluoride from Al(OH) -F and Al(OH) -F is below the Chinese Class-I Industrial Wastewater Discharge Standard for fluoride (<10 mg·L ). This study demonstrates that the Al(OH) solid wastes generated in fluoride removal process could be potentially utilized as a adsorbent for Cd(II) removal.

关键词： Al(OH)3     fluoride     cadmium     adsorption     reclamation     sequential extraction    

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A “Sequential Design of Simulations” approach for exploiting and calibrating discrete element simulations

《化学科学与工程前沿（英文）》 2022年 第16卷 第6期   页码 874-885 doi: 10.1007/s11705-021-2131-1

摘要： The flow behaviours of cohesive particles in the ring shear test were simulated and examined using discrete element method guided by a design of experiments methodology. A full factorial design was used as a screening design to reveal the effects of material properties of partcles. An augmented design extending the screening design to a response surface design was constructed to establish the relations between macroscopic shear stresses and particle properties. It is found that the powder flow in the shear cell can be classified into four regimes. Shear stress is found to be sensitive to particle friction coefficient, surface energy and Young’s modulus. A considerable fluctuation of shear stress is observed in high friction and low cohesion regime. In high cohesion regime, Young’s modulus appears to have a more significant effect on the shear stress at the point of incipient flow than the shear stress during the pre-shear process. The predictions from response surface designs were validated and compared with shear stresses measured from the Schulze ring shear test. It is found that simulations and experiments showed excellent agreement under a variety of consolidation conditions, which verifies the advantages and feasibility of using the proposed “Sequential Design of Simulations” approach.

关键词： discrete element method     cohesive materials     parameter calibration     ring shear cell     design of experiments    

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Effects of eggshell addition on calcium-deficient acid soils contaminated with heavy metals

Weiqi Luo, Yanping Ji, Lu Qu, Zhi Dang, Yingying Xie, Chengfang Yang, Xueqin Tao, Jianmin Zhou, Guining Lu

《环境科学与工程前沿（英文）》 2018年 第12卷 第3期 doi: 10.1007/s11783-018-1026-y

摘要： In this study, effects of water conditions (flooded, wet, or dry) and eggshell dosages (0, 0.1, 1.0, and 10.0 g/kg soil, respectively) on pH variation, content of unavailable state of heavy metals, form of heavy metals, and available nutritious element calcium (Ca) in acid soils contaminated with heavy metals were investigated, respectively. The soil samples were continuously cultivated indoors and analyzed by toxicity characteristic leaching procedure and community bureau of reference (BCR) sequential extraction procedure. The results showed that the addition of eggshell could effectively improve the pH of acid soil and increase it to neutral level. Moreover, the contents of unavailable state of heavy metals Cu, Zn, and Cd increased significantly. Furthermore, when the soil was cultivated under the flooded condition with 1.0 g/kg eggshell, the unavailable state of Cu, Zn, and Cd increased the most, and these heavy metals were transformed into residual state. On the other hand, the amount of available state of Ca increased to 432.19 from 73.34 mg/kg with the addition of 1.0 g/kg eggshell, which indicated that the addition of eggshell dramatically improved the available state of Ca. Therefore, eggshell could ameliorate the soil environment as it led to the decrease of available heavy metals and improvement of fertilization effectively. In a word, this study indicates that the addition of eggshell would be a new potential method for remediation of acid field soils contaminated with heavy metals.

关键词： Heavy metals     Eggshell     Acid soil remediation     BCR sequential extraction    

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Entity and relation extraction with rule-guided dictionary as domain knowledge

《工程管理前沿（英文）》   页码 610-622 doi: 10.1007/s42524-022-0226-0

摘要： Entity and relation extraction is an indispensable part of domain knowledge graph construction, which can serve relevant knowledge needs in a specific domain, such as providing support for product research, sales, risk control, and domain hotspot analysis. The existing entity and relation extraction methods that depend on pretrained models have shown promising performance on open datasets. However, the performance of these methods degrades when they face domain-specific datasets. Entity extraction models treat characters as basic semantic units while ignoring known character dependency in specific domains. Relation extraction is based on the hypothesis that the relations hidden in sentences are unified, thereby neglecting that relations may be diverse in different entity tuples. To address the problems above, this paper first introduced prior knowledge composed of domain dictionaries to enhance characters’ dependence. Second, domain rules were built to eliminate noise in entity relations and promote potential entity relation extraction. Finally, experiments were designed to verify the effectiveness of our proposed methods. Experimental results on two domains, including laser industry and unmanned ship, showed the superiority of our methods. The F1 value on laser industry entity, unmanned ship entity, laser industry relation, and unmanned ship relation datasets is improved by +1%, +6%, +2%, and +1%, respectively. In addition, the extraction accuracy of entity relation triplet reaches 83% and 76% on laser industry entity pair and unmanned ship entity pair datasets, respectively.

关键词： entity extraction     relation extraction     prior knowledge     domain rule    

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Impact of selection of DC base values and DC link control strategies on sequential AC-DC power-flow convergence

Shagufta KHAN,Suman BHOWMICK

《能源前沿（英文）》 2015年 第9卷 第4期   页码 399-412 doi: 10.1007/s11708-015-0374-6

摘要： This paper demonstrates the convergence of the integrated AC-DC power-flow algorithm as affected by the selection of different base values for the DC quantities and adoption of different control strategies for the DC link. For power-flow modeling of integrated AC-DC systems, the base values of the various DC quantities can be defined in several ways, giving rise to different sets of per-unit system equations. It is observed that different per-unit system models affect the convergence of the power-flow algorithm differently. In a similar manner, the control strategy adopted for the DC link also affects the power-flow convergence. The sequential method is used to solve the DC variables in the Newton Raphson (NR) power flow model, where AC and DC systems are solved separately and are coupled by injecting an equivalent amount of real and reactive power at the terminal AC buses. Now, for a majority of the possible control strategies, the equivalent real and reactive power injections at the concerned buses can be computed a-priori and are independent of the NR iterative loop. However, for a few of the control strategies, the equivalent reactive power injections cannot be computed a-priori and need to be computed in every NR iteration. This affects the performance of the iterative process. Two different per-unit system models and six typical control strategies are taken into consideration. This is validated by numerous case studies conducted on the IEEE 118-bus and 300-bus test systems.

关键词： AC-DC power-flow     Newton-Raphson method     high voltage direct current (HVDC) control strategy    

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Comparison of sequential with intimate coupling of photolysis and biodegradation for benzotriazole

Shunan Shan, Yuting Zhang, Yining Zhang, Lanjun Hui, Wen Shi, Yongming Zhang, Bruce E. Rittmann

《环境科学与工程前沿（英文）》 2017年 第11卷 第6期 doi: 10.1007/s11783-017-0953-3

摘要： Benzotriazole (BTA) is an emerging contaminant that also is a recalcitrant compound. Sequential and intimate coupling of UV-photolysis with biodegradation were investigated for their impacts on BTA removal and mineralization in aerobic batch experiments. Special attention was given to the role of its main photolytic products, which were aminophenol (AP), formic acid (FA), maleic acid (MA), and phenazine (PHZ). Experiments with sequential coupling showed that BTA biodegradation was accelerated by photolytic pretreatment up to 9 min, but BTA biodegradation was slowed with longer photolysis. FA and MA accelerated BTA biodegradation by being labile electron-donor substrates, but AP and PHZ slowed the rate because of inhibition due to their competition for intracellular electron donor. Because more AP and PHZ accumulated with increasing photolysis time, their inhibitory effects began to dominate with longer photolysis time. Intimately coupling photolysis with biodegradation relieved the inhibition effect, because AP and PHZ were quickly biodegraded and did not accumulate, which accentuated the beneficial effect of FA and MA.

关键词： Benzotriazole     Photolysis     Biodegradation     Inhibition     Electron donor    

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An extraction- assay system: Evaluation on flavonols in plant resistance to Pb and Cd by supercriticalextraction- gas chromatography

Xu Zhang, Huanhuan Yang, Xinlei Wang, Wen Song, Zhaojie Cui

《环境科学与工程前沿（英文）》 2018年 第12卷 第4期 doi: 10.1007/s11783-018-1059-2

摘要：

SFE-GC system is established for flavonols assessment.

Optimal parameters of SFE-GC are evaluated and determined.

Quercetin and kaempferol are detected in plant under heavy metal stress.

Gene expression analysis shows consistent regularity with content of flavonols.

ROS level is applied for elaborating the plant resistance status.

关键词： Flavonols     Heavy metal     Supercritical carbon dioxide extraction (SFE)     GC     Plant resistance    

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Thermodynamic analysis of ethanol synthesis from hydration of ethylene coupled with a sequential reaction

Jie Gao, Zhikai Li, Mei Dong, Weibin Fan, Jianguo Wang

《化学科学与工程前沿（英文）》 2020年 第14卷 第5期   页码 847-856 doi: 10.1007/s11705-019-1848-6

摘要： Coal-based ethanol production by hydration of ethylene is limited by the low equilibrium ethylene conversion at elevated temperature. To improve ethylene conversion, coupling hydration of ethylene with a potential ethanol consumption reaction was analyzed thermodynamically. Five reactions have been attempted and compared: (1) dehydration of ethanol to ethyl ether ( ), (2) dehydrogenation of ethanol to acetaldehyde ( ), (3) esterification of acetic acid with ethanol ( ), (4) dehydrogenation of ethanol to ethyl acetate ( ), and (5) oxidative dehydrogenation of ethanol to ethyl acetate ( ). The equilibrium constants and equilibrium distributions of the coupled reactions were calculated and the effects of feed composition, temperature and pressure upon the ethylene equilibrium conversion were examined. The results show that dehydrogenation of ethanol to acetaldehyde has little effect on ethylene conversion, whereas for dehydrogenation of ethanol to acetaldehyde and ethyl acetate, ethylene conversion can be improved from 8% to 12.8% and 18.5%, respectively, under conditions of H O/C H = 2, 10 atm and 300°C. The esterification of acetic acid with ethanol can greatly enhance the ethylene conversion to 22.5%; in particular, ethylene can be actually completely converted to ethyl acetate by coupling oxidative dehydrogenation of ethanol.

关键词： ethylene     ethanol     thermodynamics     coupling    

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Feature extraction from slice data for reverse engineering

ZHANG Yingjie, LU Shangning

《机械工程前沿（英文）》 2007年 第2卷 第1期   页码 25-31 doi: 10.1007/s11465-007-0004-z

摘要： A new approach to feature extraction for slice data points is presented. The reconstruction of objects is performed as follows. First, all contours in each slice are extracted by contour tracing algorithms. Then the data points on the contours are analyzed, and the curve segments of the contours are divided into three categories: straight lines, conic curves and B-spline curves. The curve fitting methods are applied for each curve segment to remove the unwanted points with pre-determined tolerance. Finally, the features, which consist of the object and connection relations among them, are founded by matching the corresponding contours in adjacent slices, and 3D models are reconstructed based on the features. The proposed approach has been implemented in OpenGL, and the feasibility of the proposed method has been verified by several cases.

关键词： feasibility     corresponding     B-spline     pre-determined tolerance     extraction    

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A microextraction approach for rapid extraction and separation of Mn(II) and Co(II) using saponified

《化学科学与工程前沿（英文）》 2022年 第16卷 第6期   页码 963-972 doi: 10.1007/s11705-021-2081-7

摘要： In this paper, we proposed a microextraction approach for the extraction and separation of Mn(II) and Co(II) from sulfate solution simulating leachate of spent lithium-ion battery cathode materials using saponified di-(2-ethylhexyl)phosphoric acid system. The effects of the following operational variables were investigated: equilibrium pH, tri-n-butyl phosphate concentration, saponification rate, two-phase ratio and residence time. The results showcased that the microextractor can reach the extraction equilibrium within 20 s, thereby greatly reducing necessary extraction time comparing to that of conventional processes. The volumetric mass transfer coefficient showed 8–21 times larger than that of batch device. With the help of microextractor, 95% of Mn(II) was extracted with a single theoretical stage at a chosen two-phase ratio of 3:1, and the separation factor βMn/Co was as large as 65.5. In the subsequent stripping step, more than 99% of manganese from loaded phase was easily stripped under optimal conditions. The microextraction approach greatly enhances the mass transfer while enabling a continuous and controllable extraction process within a simple structure design. When extracting spent electrode material with microextractors, the comprehensive recovery of mangenese can reach 96%. The microextraction approach has a good applicability in the spent lithium-ion battery cathode materials recycling at both bench and industrial scales.

关键词： extraction equilibrium     mass transfer coefficient     microextraction     multicomponent extraction     di-(2-ethylhexyl)phosphoric acid    

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Successful management of seven cases of critical COVID-19 with early noninvasive–invasive sequential

Mian Peng, Xueyan Liu, Jinxiu Li, Di Ren, Yongfeng Liu, Xi Meng, Yansi Lyu, Ronglin Chen, Baojun Yu, Weixiong Zhong

《医学前沿（英文）》 2020年 第14卷 第5期   页码 674-680 doi: 10.1007/s11684-020-0796-3

摘要： We report the clinical and laboratory findings and successful management of seven patients with critical coronavirus disease 2019 (COVID-19) requiring mechanical ventilation (MV). The patients were diagnosed based on epidemiological history, clinical manifestations, and nucleic acid testing. Upon diagnosis with COVID-19 of critical severity, the patients were admitted to the intensive care unit, where they received early noninvasive–invasive sequential ventilation, early prone positioning, and bundle pharmacotherapy regimen, which consists of antiviral, anti-inflammation, immune-enhancing, and complication-prophylaxis medicines. The patients presented fever ( = 7, 100%), dry cough ( = 3, 42.9%), weakness ( = 2, 28.6%), chest tightness ( = 1, 14.3%), and/or muscle pain ( = 1, 14.3%). All patients had normal or lower than normal white blood cell count/lymphocyte count, and chest computed tomography scans showed bilateral patchy shadows or ground glass opacity in the lungs. Nucleic acid testing confirmed COVID-19 in all seven patients. The median MV duration and intensive care unit stay were 9.9 days (interquartile range, 6.5–14.6 days; range, 5–17 days) and 12.9 days (interquartile range, 9.7–17.6 days; range, 7–19 days), respectively. All seven patients were extubated, weaned off MV, transferred to the common ward, and discharged as of the writing of this report. Thus, we concluded that good outcomes for patients with critical COVID-19 can be achieved with early noninvasive–invasive sequential ventilation and bundle pharmacotherapy.

关键词： COVID-19     noninvasive–invasive sequential ventilation     bundle pharmacotherapy    

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Performance evaluation of an improved biomass-fired cogeneration system simultaneously using extraction

《能源前沿（英文）》 2022年 第16卷 第2期   页码 321-335 doi: 10.1007/s11708-021-0741-4

摘要： An advanced cogeneration system based on biomass direct combustion was developed and its feasibility was demonstrated. In place of the traditional single heat source (extraction steam), the extraction steam from the turbine, the cooling water from the plant condenser, and the low-pressure feedwater from the feedwater preheating system were collectively used for producing district heat in the new scheme. Hence, a remarkable energy-saving effect could be achieved, improving the overall efficiency of the cogeneration system. The thermodynamic and economic performance of the novel system was examined when taking a 35 MW biomass-fired cogeneration unit for case study. Once the biomass feed rate and net thermal production remain constant, an increment of 1.36 MW can be expected in the net electric production, because of the recommended upgrading. Consequently, the total system efficiency and effective electrical efficiency augmented by 1.23 and 1.50 percentage points. The inherent mechanism of performance enhancement was investigated from the energy and exergy aspects. The economic study indicates that the dynamic payback period of the retrofitting project is merely 1.20 years, with a net present value of 5796.0 k$. In conclusion, the proposed concept is validated to be advantageous and profitable.

关键词： biomass-fired cogeneration     district heat production system     absorption heat pump     extraction steam     cooling water     low-pressure feedwater    

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标题 作者 时间 类型 操作

mechanisms of diphenylarsinic acid on natural magnetite and siderite: Evidence from sorption kinetics, sequentialextraction and extended X-ray absorption fine-structure spectroscopy analysis

期刊论文

Field evidence of decreased extractability of copper and nickel added to soils in 6-year field experiments

Bao Jiang, Dechun Su, Xiaoqing Wang, Jifang Liu, Yibing Ma

期刊论文

Control strategies for disinfection byproducts by ion exchange resin, nanofiltration and their sequential

期刊论文

Utilization of aluminum hydroxide waste generated in fluoride adsorption and coagulation processes for adsorptive removal of cadmium ion

Jiawei JU,Ruiping LIU,Zan HE,Huijuan LIU,Xiwang ZHANG,Jiuhui QU

期刊论文

A “Sequential Design of Simulations” approach for exploiting and calibrating discrete element simulations

期刊论文

Effects of eggshell addition on calcium-deficient acid soils contaminated with heavy metals

Weiqi Luo, Yanping Ji, Lu Qu, Zhi Dang, Yingying Xie, Chengfang Yang, Xueqin Tao, Jianmin Zhou, Guining Lu

期刊论文

Entity and relation extraction with rule-guided dictionary as domain knowledge

期刊论文

Impact of selection of DC base values and DC link control strategies on sequential AC-DC power-flow convergence

Shagufta KHAN,Suman BHOWMICK

期刊论文

Comparison of sequential with intimate coupling of photolysis and biodegradation for benzotriazole

Shunan Shan, Yuting Zhang, Yining Zhang, Lanjun Hui, Wen Shi, Yongming Zhang, Bruce E. Rittmann

期刊论文

An extraction- assay system: Evaluation on flavonols in plant resistance to Pb and Cd by supercriticalextraction- gas chromatography

Xu Zhang, Huanhuan Yang, Xinlei Wang, Wen Song, Zhaojie Cui

期刊论文

Thermodynamic analysis of ethanol synthesis from hydration of ethylene coupled with a sequential reaction

Jie Gao, Zhikai Li, Mei Dong, Weibin Fan, Jianguo Wang

期刊论文

Feature extraction from slice data for reverse engineering

ZHANG Yingjie, LU Shangning

期刊论文

A microextraction approach for rapid extraction and separation of Mn(II) and Co(II) using saponified

期刊论文

Successful management of seven cases of critical COVID-19 with early noninvasive–invasive sequential

Mian Peng, Xueyan Liu, Jinxiu Li, Di Ren, Yongfeng Liu, Xi Meng, Yansi Lyu, Ronglin Chen, Baojun Yu, Weixiong Zhong

期刊论文

Performance evaluation of an improved biomass-fired cogeneration system simultaneously using extraction

期刊论文