资源类型

期刊论文 278

年份

2023 31

2022 19

2021 8

2020 14

2019 9

2018 8

2017 25

2016 11

2015 18

2014 6

2013 8

2012 9

2011 8

2010 22

2009 12

2008 15

2007 20

2006 6

2005 2

2004 4

展开 ︾

关键词

内禀尺度 2

地震预测 2

大型化成藏 2

海上风电 2

4D CAD 1

Agent 1

CCUS 1

CO 1

CO2 捕集 1

CO2利用 1

CO2封存 1

EBL 1

FIB 1

ICP 1

ISO 9705 1

SWAT-WF模块 1

一阶分析法 1

三重盈余 1

两个市场两种资源 1

展开 ︾

检索范围:

排序: 展示方式:

Adsorption of phosphate on magnetite-enriched particles (MEP) separated from the mill scale

Muhammad Kashif Shahid, Yunjung Kim, Young-Gyun Choi

《环境科学与工程前沿(英文)》 2019年 第13卷 第5期 doi: 10.1007/s11783-019-1151-2

摘要: MEP were separated from mill scale at low magnetic intensity i.e., 300 to 500 gauss. The phosphate adsorption capacity of MEP was determined 6.41 mg/g. MEP packed-bed columns were successfully regenerated with alkaline solution. Phosphate is a major pollutant in water, causing serious environmental and health consequences. In present study, the phosphate adsorption on novel magnetite-enriched particles (MEP) was comprehensively investigated. A new method and device were introduced for the separation of MEP from the mill scale at low magnetic intensity. Particles were characterized with different techniques such as XRD, XRF, SEM and EDS. The XRD and XRF analysis of MEP identified the dominant existence of crystalline magnetite. Furthermore, the morphological analysis of MEP confirmed the agglomerate porous morphology of magnetite. Oxygen and iron, the main constituents of magnetite were acknowledged during the elemental analysis using EDS. The phosphate adsorption on MEP is well explained using various isotherm and kinetic models, exhibiting the monolayer adsorption of phosphate on the surface of MEP. The maximum adsorption capacity was determined 6.41 mg/g. Based on particle size (45–75 and 75–150 µm) and empty bed contact time (1 and 2 h), four columns were operated for 54 days. MEP were appeared successful to remove all phosphate concentration from the column influent having 2 mg/L concentration. The operated column reactors were successfully regenerated with alkaline solution. The results indicated potential for practical application of the MEP for phosphate removal.

关键词: Adsorption     Magnetite     Mill-scale     Phosphate     Wastewater treatment    

Optimization of thermophilic anaerobic-aerobic treatment system for Palm Oil Mill Effluent (POME)

Yijing CHAN,Meifong CHONG,Chunglim LAW

《环境科学与工程前沿(英文)》 2015年 第9卷 第2期   页码 334-351 doi: 10.1007/s11783-014-0626-4

摘要: Optimization of an integrated anaerobic-aerobic bioreactor (IAAB) treatment system for the reduction of organic matter (Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD) and Total Suspended Solids (TSS) concentrations) in Palm Oil Mill Effluent (POME) to legal standards with high methane yield was performed for the first time under thermophilic condition (50°C–55°C) by using response surface methodology (RSM). The experiments were conducted based on a central composite rotatable design (CCRD) with three independent operating variables, organic loading rates in anaerobic compartment (OLR ) and mixed liquor volatile suspended solids (MLVSS) concentration in anaerobic (MLVSS ) and aerobic compartments (MLVSS ). The optimum conditions for the POME treatment were determined as OLR of 15.6 g COD·L ·d , MLVSS of 43100 mg·L , and MLVSS of 18600 mg·L , where high aerobic COD, BOD and TSS removal efficiencies of 96.3%, 97.9%, and 98.5% were achieved with treated BOD of 56 mg·L and TSS of 28 mg·L meeting the discharge standard. This optimization study successfully achieved a reduction of 42% in the BOD concentrations of the final treated effluent at a 48% higher OLR as compared to the previous works. Besides, thermophilic IAAB system scores better feasibility and higher effectiveness as compared to the optimized mesophilic system. This is due to its higher ability to handle high OLR with higher overall treatment efficiencies (more than 99.6%), methane yield (0.31 L CH ·g COD ) and purity of methane (67.5%). Hence, these advantages ascertain the applicability of thermophilic IAAB in the POME treatment or even in other high-strength wastewaters treatment.

关键词: palm oil mill effluent (POME)     anaerobic     aerobic     thermophilic     biogas     optimization    

适用于轧钢过程的计算机控制系统

孙一康

《中国工程科学》 2000年 第2卷 第1期   页码 73-76

摘要:

轧钢自动化,特别是带钢热连轧自动化,要求计算机控制系统具有高速控制、高速通信能力。为了推动我国轧钢自动化技术的发展,在分析国外系统发展的基础上,自行设计和集成了适用于"快速"过程的分布式计算机控制系统,这一系列已在几台热连轧机上得到应用,文章对这一系统进行了介绍。

关键词: 轧钢自动化     带钢热连轧自动化     分布式计算机控制系统     系统集成    

2300轧机上支承辊轴承座强度分析

王化川,王爱玲

《中国工程科学》 2001年 第3卷 第1期   页码 83-84

摘要:

论述了在AGC改造中上支承辊轴承座的改造,利用有限单元进行强度校核,并提出最优结果。

关键词: 轧机改造     有限单元     伺服油缸    

Elongation distribution between tension leveler and temper mill for pickling line 2030 in Baosteel

LIU Xiancui, SU Lanhai, LI Zhongfu, ZHANG Qingdong, FU Zhilin, HE Chun

《机械工程前沿(英文)》 2007年 第2卷 第3期   页码 297-300 doi: 10.1007/s11465-007-0052-4

摘要: Research into plate elongation distribution between the tension leveler and temper mill for pickling line 2030 at Baosteel is conducted. The study, which involved performance testing of mechanics, is designed at different elongation distributions and analyzed from many aspects. Finally, the optimal elongation of the tension leveler and temper mill is given.

关键词: elongation distribution     Baosteel     Research     different elongation     performance    

Bioleaching of copper from pre and post thermally activated low grade chalcopyrite contained ball mill

Sandeep PANDA, Nilotpala PRADHAN, Umaballav MOHAPATRA, Sandeep K. PANDA, Swagat S. RATH, Danda S. RAO, Bansi D. NAYAK, Lala B. SUKLA, Barada K. MISHRA

《环境科学与工程前沿(英文)》 2013年 第7卷 第2期   页码 281-293 doi: 10.1007/s11783-013-0484-5

摘要: Bioleaching of a low grade chalcopyrite (ball mill spillage material) was tested for copper recovery in shake flasks. The original samples (as received) were thermally activated (600°C, 30 min) to notice the change in physico-chemical and mineralogical characteristics of the host rock and subsequently its effect on copper recovery. A mixed culture of acidophilic chemolithotrophic bacterial consortium predominantly entailing strain was used for bioleaching studies and optimization of process parameters of both original and thermally activated samples. Mineralogical characterization studies indicated the presence of chalcopyrite, pyrite in the silicate matrix of the granitic rock. Field emission scanning electron microscopy coupled with Energy dispersive spectroscopy (FESEM-EDS) and X-ray Fluorescence (XRF) analysis indicated mostly SiO . With pH 2, pulp density 10% w/v, inoculum 10% v/v, temperature 30°C, 150 r·min , 49% copper could be recovered in 30 days from the finest particle size (-1+ 0.75 mm) of the original spillage sample. Under similar conditions 95% copper could be recovered from the thermally activated sample with the same size fraction in 10 days. The study revealed that thermal activation leads to volume expansion in the rock with the development of cracks, micro and macro pores on its surface, thereby enabling bacterial solution to penetrate more easily into the body, facilitating enhanced copper dissolution.

关键词: ball mill spillage     thermal activation     bioleaching     copper    

Advantageous mechanochemical synthesis of copper(I) selenide semiconductor, characterization, and properties

《化学科学与工程前沿(英文)》 2022年 第16卷 第3期   页码 433-442 doi: 10.1007/s11705-021-2066-6

摘要: Copper(I) selenide-nanocrystalline semiconductor was synthesized via one-step mechanochemical synthesis after 5 min milling in a planetary ball mill. The kinetics of synthesis was followed by X-ray powder diffraction analysis and specific surface area measurements of milled 2Cu/Se mixtures. The X-ray diffraction confirmed the orthorhombic crystal structure of Cu2Se with the crystallite size ~25 nm. The surface chemical structure was studied by X-ray photoelectron spectroscopy, whereby the binding energy of the Cu 2p and Se 3d signals corresponded to Cu+ and Se2– oxidation states. Transmission electron microscopy revealed agglomerated nanocrystals and confirmed their orthorhombic structure, as well. The optical properties were studied utilizing ultraviolet-visible spectroscopy and photoluminescence spectroscopy. The direct bandgap energy 3.7 eV indicated a blue-shift phenomenon due to the quantum size effect. This type of Cu2Se synthesis can be easily adapted to production dimensions using an industrial vibratory mill. The advantages of mechanochemical synthesis represent the potential for inexpensive, environmentally-friendly, and waste-free manufacturing of Cu2Se.

关键词: Cu2Se     berzelianite     nanocrystalline semiconductor     mechanochemical synthesis     planetary ball mill    

Life-cycle analysis of energy use and greenhouse gas emissions of gas-to-liquid fuel pathway from steel mill

Xunmin OU, Xu ZHANG, Qian ZHANG, Xiliang ZHANG

《能源前沿(英文)》 2013年 第7卷 第3期   页码 263-270 doi: 10.1007/s11708-013-0263-9

摘要: The LanzaTech process can convert carbon monoxide-containing gases produced by industries, such as steel manufacturing, into valuable fuel products. The life-cycle analysis (LCA) of energy use and greenhouse gas emissions from the LanzaTech process has been developed for a Chinese setting using the original Tsinghua China Automotive LCA model along with a customized module developed principally for the process. The LCA results demonstrate that LanzaTech gas-to-liquid (GTL) processing in China’s steel manufacturing is favorable in terms of life-cycle fossil energy and can reduce greenhouse gas emissions by approximately 50% compared with the conventional petroleum gasoline. The LanzaTech process, therefore, shows advantages in both energy-savings and a reduction in greenhouse gas emissions when compared with most bio-ethanol production pathways in China.

关键词: life-cycle analysis (LCA)     gas-to-liquid (GTL)     LanzaTech process    

Structure controlling and process scale-up in the fabrication of nanomaterials

Chunzhong LI,

《化学科学与工程前沿(英文)》 2010年 第4卷 第1期   页码 18-25 doi: 10.1007/s11705-009-0305-3

摘要: Nanotechnology is already having a significant commercial impact, and will very certainly have a much greater impact in the future. The research on process engineering and scale-up will be very important for the commercial production and application of nanomaterials, because the properties and structure of nanomaterials are not only determined by the nucleation and growth process, but also strongly affected by the engineering properties, such as the mixing, the heat and mass transfer, and also the distribution of temperature, concentration, etc. This paper will present some research work in our laboratory on the fabrication of nanomaterials. Based on the chemical engineering principle and methods, many kinds of novel nanomaterials can be synthesized and their structure can be easily controlled through adjusting the parameters of the fluid mixing, and the distribution of temperature, residence time and concentration, etc. By using the micro-mixing, heat and mass transfer and reaction control methods, the host-guest nanocomposites have been assembled and assumed as the novel electroanalytical sensing nanobiocomposite materials. Based on the principles of chemical engineering, the manufacturing technologies for magnetic powders, calcium carbonate, and titanium dioxide have been developed for commercial-scale production, and the largest production scale has reached 15 kt/year.

关键词: scale-up     significant commercial     electroanalytical     engineering     laboratory    

Large-scale App privacy governance

《工程管理前沿(英文)》   页码 640-652 doi: 10.1007/s42524-022-0228-y

摘要: Recently, the problem of mobile applications (Apps) leaking users’ private information has aroused wide concern. As the number of Apps continuously increases, effective large-scale App governance is a major challenge. Currently, the government mainly filters out Apps with potential privacy problems manually. Such approach is inefficient with limited searching scope. In this regard, we propose a quantitative method to filter out problematic Apps on a large scale. We introduce Privacy Level (P-Level) to measure an App’s probability of leaking privacy. P-Level is calculated on the basis of Permission-based Privacy Value (P-Privacy) and Usage-based Privacy Value (U-Privacy). The former considers App permission setting, whereas the latter considers App usage. We first illustrate the privacy value model and computation results of both values based on real-world dataset. Subsequently, we introduce the P-Level computing model. We also define the P-Level computed on our dataset as the PL standard. We analyze the distribution of average usage and number of Apps under the levels given in the PL standard, which may provoke insights into the large-scale App governance. Through P-Privacy, U-Privacy, and P-Level, potentially problematic Apps can be filtered out efficiently, thereby making up for the shortcoming of being manual.

关键词: privacy risk     Privacy Level     quantification     large-scale App governance    

A novel approach to minimizing material loss for computer numerical control flank-regrinding of worn end mills

《机械工程前沿(英文)》 2023年 第18卷 第3期 doi: 10.1007/s11465-023-0757-z

摘要: Flanks of end mills are prone to wear in a long machining process. Regrinding is widely used in workshops to restore the flank to an original-like state. However, the traditional method involves material waste by trial and error and dramatically decreases the potential regrinding. Moreover, over-cut would happen to the flutes of worn cutters in the regrinding processes because of improper wheel path. This study presented a new approach to planning the wheel path for regrinding worn end mills to minimize material loss and recover the over-cut. In planning, a scaling method was developed to determine the maximum size of the new cutter according to the similarity of cutter shapes before and after regrinding. Then, the wheel path is first generated by envelope theory to regrind the worn area with a four-axis computer numerical control grinder according to the new size of cutters. Moreover, a second regrinding strategy is applied to recover the flute shape over-cut in the first grinding. Finally, the proposed method is verified by an experiment. Results showed that the proposed approach could save 25% of cutter material compared with the traditional method and ensure at least three regrinding times. This work effectively provides a general regrinding solution for the worn flank with maximum material-saving and regrinding period.

关键词: flank-regrinding     worn end mill     wheel position and orientation     material loss     over-cut    

On the added value of multi-scale modeling of concrete

《结构与土木工程前沿(英文)》 2022年 第16卷 第1期   页码 1-23 doi: 10.1007/s11709-021-0790-0

摘要: This review of the added value of multi-scale modeling of concrete is based on three representative examples. The first one is concerned with the analysis of experimental data, taken from four high-dynamic tests. The structural nature of the high-dynamic strength increase can be explained by using a multi-scale model. It accounts for the microstructure of the specimens. The second example refers to multi-scale thermoelastic analysis of concrete pavements, subjected to solar heating. A sensitivity analysis with respect to the internal relative humidity (RH) of concrete has underlined the great importance of the RH for an assessment of the risk of microcracking of concrete. The third example deals with multi-scale structural analysis of a real-scale test of a segmental tunnel ring. It has turned out that multi-scale modeling of concrete enables more reliable predictions of crack opening displacements in tunnel segments than macroscopic models taken from codes of practice. Overall, it is concluded that multi-scale models have indeed a significant added value. However, its degree varies with these examples. In any case, it can be assessed by means of a comparison of the results from three sources, namely, multi-scale structural analysis, conventional structural analysis, and experiments.

关键词: experiments     multi-scale analysis     conventional structural analysis     concrete     reinforced concrete    

Large Scale Infrastructure Projects: The Art of Project or Change Management?

Geert Letens,Kurt Verweire,Peter De Prins

《工程管理前沿(英文)》 2016年 第3卷 第3期   页码 197-202 doi: 10.15302/J-FEM-2016033

摘要: Although it is generally understood that change is a fundamental component of managing projects in the construction industry in general and an inevitable challenge for large scale infrastructure project in particular, there has been little to no attention in the literature to understand change in this context from a more holistic perspective. For this purpose, this work looks at change through the eyes of a framework of six batteries of change that seem essential to charge an organization’s capabilities for change. The framework brings together the expertise of four specialists that all have developed their insights over many years of study and practice, and has been validated through an extensive review of the management literature on organization development and change. Reflections on the application of this model in the construction industry and in large scale infrastructure projects demonstrate that energizing organizations to successfully deal with change goes beyond the traditional techniques of managing change from a program or project management perspective. Assessing the six batteries of change in this context can help organizations to develop capabilities for change that build change energy by balancing formal/rational methods with informal/emotional interventions at both a local (department/subproject) and global (business) level.

关键词: large scale project management     organization development and change     batteries of change model    

Large-scale model test study on the water pressure resistance of construction joints of karst tunnel

《结构与土木工程前沿(英文)》   页码 1249-1263 doi: 10.1007/s11709-023-0974-x

摘要: Model tests and numerical calculations were adopted based on the New Yuanliangshan tunnel project to investigate the water pressure resistance of lining construction joints in high-pressure and water-rich karst tunnels. A large-scale model test was designed and conducted, innovatively transforming the external water pressure of the lining construction joint into internal water pressure. The effects of the embedded position and waterstop type on the water pressure resistance of the construction joint were analyzed, and the reliability of the model test was verified via numerical calculations. The results show that using waterstops can significantly improve the water pressure resistance of lining construction joints. The water pressure resistance of the lining construction joint is positively correlated with the lining thickness and embedded depth of the waterstop. In addition, the type of waterstop significantly influences the water pressure resistance of lining construction joints. The test results show that the water pressure resistance of the embedded transverse reinforced waterstop is similar to that of the steel plate waterstop, and both have more advantages than the rubber waterstop. The water pressure resistance of the construction joint determined via numerical calculations is similar to the model test results, indicating that the model test results have high accuracy and reliability. This study provides a reference for similar projects and has wide applications.

关键词: karst tunnel     lining construction joint     water pressure resistance     large-scale model test     numerical calculations    

Stabilization treatment of contaminated soil: a field-scale application in Shanghai, China

Changbo ZHANG, Qishi LUO, Chunnu GENG, Zhongyuan LI

《环境科学与工程前沿(英文)》 2010年 第4卷 第4期   页码 395-404 doi: 10.1007/s11783-010-0271-5

摘要: Stabilization is one of the best demonstrated available technologies for treating toxic pollutants in soils and has been used worldwide but is rarely used for treatment of contaminated sites in China despite many bench-scale studies. Here, a field-scale application of stabilization treatment in Shanghai, China was summarized to demonstrate the whole engineering process and the key technical issues regarding stabilization of contaminated soil. A site contaminated with arsenic (As) and polycyclic aromatic hydrocarbons (PAHs), formerly used as a lighting plant in Shanghai, was chosen as the demonstration site. Stabilizing measures were taken to treat the contaminated soil to reuse the site for residential purposes. The whole engineering remediation process consisted of phase I environmental site assessment (ESA) and phase II ESA, quantitative human health risk assessment, remediation alternatives evaluation, bench-scale testing, remedial design, engineering implementation, and post-remediation assessment. A third party conducted evaluation monitoring indicated desirable results were achieved via the stabilization treatment. In addition, some technical obstacles related to soil stabilization treatment were discussed, including soil quality evaluation, stabilization effectiveness validation, and soil reuse assessment.

关键词: stabilization     contaminated soil     field-scale demonstration     technical obstacles    

标题 作者 时间 类型 操作

Adsorption of phosphate on magnetite-enriched particles (MEP) separated from the mill scale

Muhammad Kashif Shahid, Yunjung Kim, Young-Gyun Choi

期刊论文

Optimization of thermophilic anaerobic-aerobic treatment system for Palm Oil Mill Effluent (POME)

Yijing CHAN,Meifong CHONG,Chunglim LAW

期刊论文

适用于轧钢过程的计算机控制系统

孙一康

期刊论文

2300轧机上支承辊轴承座强度分析

王化川,王爱玲

期刊论文

Elongation distribution between tension leveler and temper mill for pickling line 2030 in Baosteel

LIU Xiancui, SU Lanhai, LI Zhongfu, ZHANG Qingdong, FU Zhilin, HE Chun

期刊论文

Bioleaching of copper from pre and post thermally activated low grade chalcopyrite contained ball mill

Sandeep PANDA, Nilotpala PRADHAN, Umaballav MOHAPATRA, Sandeep K. PANDA, Swagat S. RATH, Danda S. RAO, Bansi D. NAYAK, Lala B. SUKLA, Barada K. MISHRA

期刊论文

Advantageous mechanochemical synthesis of copper(I) selenide semiconductor, characterization, and properties

期刊论文

Life-cycle analysis of energy use and greenhouse gas emissions of gas-to-liquid fuel pathway from steel mill

Xunmin OU, Xu ZHANG, Qian ZHANG, Xiliang ZHANG

期刊论文

Structure controlling and process scale-up in the fabrication of nanomaterials

Chunzhong LI,

期刊论文

Large-scale App privacy governance

期刊论文

A novel approach to minimizing material loss for computer numerical control flank-regrinding of worn end mills

期刊论文

On the added value of multi-scale modeling of concrete

期刊论文

Large Scale Infrastructure Projects: The Art of Project or Change Management?

Geert Letens,Kurt Verweire,Peter De Prins

期刊论文

Large-scale model test study on the water pressure resistance of construction joints of karst tunnel

期刊论文

Stabilization treatment of contaminated soil: a field-scale application in Shanghai, China

Changbo ZHANG, Qishi LUO, Chunnu GENG, Zhongyuan LI

期刊论文