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期刊论文 31

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加和原则 1

动力学 1

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模糊决策树 1

模糊认知图 1

氟化铝添加 1

混合体;积分方程;矩量法;加法定理;迭代 1

状态转移优化方法 1

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Sinks of steel in China–addition to in-use stock, export and loss

Hua GUO,Tianzhu ZHANG

《环境科学与工程前沿(英文)》 2016年 第10卷 第1期   页码 141-149 doi: 10.1007/s11783-014-0696-3

摘要: China has become the largest producer of crude steel in the world since 1996, which places the country under huge pressure in terms of resources, energy, and the environment. Examining the driver of steel demand is of great significance to the structural adjustment and sustainable development of the steel industry. The researchers calculate the steel demand in China from 2000 to 2009 based on three sinks (steel stock, export, and loss) by taking the four stages of steel life cycle (production, fabrication and manufacturing, use, and waste management and recycling) as the study object. The researchers conclude that addition to in-use stock is the main driver of steel demand and that the 10-year average addition to in-use stock accounted for 77% of the steel sinks, in which 55% of the addition occurs in the building sector, and the steel for this segment is of low strength with large consumption. Based on the analysis of existing policies, the researchers propose that the steel demand structure will develop toward diversification and that the building sector will realize the upgrade of products as soon as possible to improve construction quality. Under the pressure of rising cost for imported resources, the export ratio of steel products should be controlled appropriately. Thus, recycling economy should be developed to reduce steel losses.

关键词: steel demand     driver     Material Flow Analysis (MFA)     Substance Flow Analysis (SFA)     addition to in-use stock     steel policy    

Effect of short-term atrazine addition on the performance of an anaerobic/anoxic/oxic process

Changyong WU, Xiaoling LI, Zhiqiang CHEN, Yongzhen PENG,

《环境科学与工程前沿(英文)》 2010年 第4卷 第2期   页码 150-156 doi: 10.1007/s11783-010-0020-9

摘要: In this study, an anaerobic/anoxic/oxic (AO) wastewater treatment process was implemented to treat domestic wastewater with short-term atrazine addition. The results provided an evaluation on the effects of an accidental pollution on the operation of a wastewater treatment plant (WWTP) in relation to Chemical Oxygen Demand (COD) and biological nutrient removal. Domestic wastewater with atrazine addition in 3 continuous days was treated when steady biological nutrient removal was achieved in the AO process. The concentrations of atrazine were 15, 10, and 5mg·L on days 1, 2 and 3, respectively. The results showed that atrazine addition did not affect the removal of COD. The specific NH NO reduction rate decreased slightly due to the short-term atrazine addition. However, it did not affect the nitrogen removal due to the high nitrification and denitrification capacity of the system. Total nitrogen (TN) removal was steady, and more than 70% was removed during the period studied. The phosphorus removal rate was not affected by the short-term addition of atrazine under the applied experimental conditions. However, more poly-hydroxy-alkanoate (PHA) was generated and utilized during atrazine addition. The results of the oxygen uptake rate (OUR) showed that the respiration of nitrifiers decreased significantly, while the activity of carbon utilizers had no obvious change with the atrazine addition. Atrazine was not removed with the AO process, even via absorption by the activated sludge in the process of the short-term addition of atrazine.

关键词: biological nutrient removal     atrazine     anaerobic/anoxic/oxic (A2O) process     oxygen demand removal     oxygen uptake rate (OUR)    

Hydration, microstructure and autogenous shrinkage behaviors of cement mortars by addition of superabsorbent

Beibei SUN, Hao WU, Weimin SONG, Zhe LI, Jia YU

《结构与土木工程前沿(英文)》 2020年 第14卷 第5期   页码 1274-1284 doi: 10.1007/s11709-020-0656-x

摘要: Superabsorbent Polymer (SAP) has emerged as a topic of considerable interest in recent years. The present study systematically and quantitively investigated the effect of SAP on hydration, autogenous shrinkage, mechanical properties, and microstructure of cement mortars. Influences of SAP on hydration heat and autogenous shrinkage were studied by utilizing TAM AIR technology and a non-contact autogenous shrinkage test method. Scanning Electron Microscope (SEM) was employed to assess the microstructure evolution. Although SAP decreased the peak rate of hydration heat and retarded the hydration, it significantly increased the cumulative heat, indicating SAP helps promote the hydration. Hydration promotion caused by SAP mainly occurred in the deceleration period and attenuation period. SAP can significantly mitigate the autogenous shrinkage when the content ranged from 0 to 0.5%. Microstructure characteristics showed that pores and gaps were introduced when SAP was added. The microstructure difference caused by SAP contributed to the inferior mechanical behaviors of cement mortars treated by SAP.

关键词: Superabsorbent Polymer     mechanical properties     hydration heat     autogenous shrinkage     microstructure    

Mass loss and nutrient dynamics during litter decomposition in response to warming and nitrogen addition

Haiyan REN, Jie QIN, Baolong YAN, Alata, Baoyinhexige, Guodong HAN

《农业科学与工程前沿(英文)》 2018年 第5卷 第1期   页码 64-70 doi: 10.15302/J-FASE-2017194

摘要: Plant litter decomposition has been studied extensively in the context of both warming and increased atmospheric nitrogen deposition. However, the temporal patterns of mass loss and nutrient release in response to warming and nitrogen addition remain unclear. A 2-year decomposition experiment aimed to examine the effects of warming and nitrogen addition on decomposition rate, and nitrogen and phosphorus dynamics. The effects of warming and nitrogen addition on decomposition of litter of , a dominant species in a desert steppe of northern China, were studied. Warming and nitrogen addition significantly enhanced litter mass loss by 10% and 16%, respectively, and moreover promoted nitrogen and phosphorus release from the litter in the first year of decomposition, followed by an immobilization period. The interactive effects of warming and nitrogen addition on mass loss, nitrogen and phosphorus concentrations of litter were also found during the decomposition. This study indicates that warming and nitrogen addition increased litter mass loss through altering litter quality. These findings highlight that interactions between climate change and other global change factors could be highly important in driving decomposition responses.

关键词: climate warming     grassland     litter decomposition     nitrogen deposition     nutrient release    

Carbon-coated lithium titanate: effect of carbon precursor addition processes on the electrochemical

Shilei Ding, Zelong Jiang, Jing Gu, Hongliang Zhang, Jiajia Cai, Dongdong Wang

《化学科学与工程前沿(英文)》 2021年 第15卷 第1期   页码 148-155 doi: 10.1007/s11705-020-2022-x

摘要: In this paper, two carbon-coated lithium titanate (LTO-C1 and LTO-C2) composites were synthesized using the ball-milling-assisted calcination method with different carbon precursor addition processes. The physical and electrochemical properties of the as-synthesized negative electrode materials were characterized to investigate the effects of two carbon-coated LTO synthesis processes on the electrochemical performance of LTO. The results show that the LTO-C2 synthesized by using Li CO and TiO as the raw materials and sucrose as the carbon source in a one-pot method has less polarization during lithium insertion and extraction, minimal charge transfer impedance value and the best electrochemical performance among all samples. At the current density of 300 mA·h·g , the LTO-C2 composite delivers a charge capacity of 126.9 mA·h·g , and the reversible capacity after 300 cycles exceeds 121.3 mA·h·g in the voltage range of 1.0–3.0 V. Furthermore, the electrochemical impedance spectra show that LTO-C2 has higher electronic conductivity and lithium diffusion coefficient, which indicates the advantages in electrode kinetics over LTO and LTO-C1. The results clarify the best electrochemical properties of the carbon-coated LTO-C2 composite prepared by the one-pot method.

关键词: lithium titanate     carbon-coated     carbon precursor     synthetic process    

基于强化模糊认知图实现数据与知识协作的氟化铝添加量决策方法 Article

岳伟超, 桂卫华, 陈晓方, 曾朝晖, 谢永芳

《工程(英文)》 2019年 第5卷 第6期   页码 1060-1076 doi: 10.1016/j.eng.2019.10.005

摘要:

在铝电解过程中,添加氟化铝能降低电解质的初晶温度,从而提高电流效率。氟化铝添加量的决策是一项复杂的知识型工作,需要考虑许多相关的因素,在实际生产中主要依赖于人工经验。由于工艺人员的主观性以及铝电解槽的复杂性,基于知识或者基于数据的决策方法难以保证添加的准确性。现有的决策方法难以囊括复杂的因果关系。本文针对氟化铝添加量的决策提出了一种基于强化模糊认知图的数据与知识协作策略。在这种方法中,改进的模糊k均值和模糊决策树用于提取模糊规则,其中提取的规则用于修正专家提出的初始框架。同时,采用状态转移优化算法(STA)获取强化模糊认知图的权重。将提出的方法与已有方法进行对比,结果表明,强化模糊认知的收敛速度快于基于Hebbian学习方法、粒子群优化方法以及遗传算法。不仅如此,基于所提方法氟化铝添加量的决策准确率高于其他方法。因此,针对氟化铝添加量的决策,本文提出的方法是有效的。

关键词: 氟化铝添加     模糊认知图     学习方法     状态转移优化方法     模糊决策树    

Effects of ionic impurities on crystallization of cobalamin

Baoli SHAO, Hui CHEN, Shuang WANG, Haijun WANG, Shenmin XU,

《化学科学与工程前沿(英文)》 2010年 第4卷 第1期   页码 70-74 doi: 10.1007/s11705-009-0293-3

摘要: In this paper, the influence of two typical ionic impurities (Na and Mg) is investigated with the focused beam reflectance measurement (FBRM) technique. In this system, the on-line FBRM is used as a tool for monitoring the crystallization process of cobalamin by measuring the chord length distribution of particles and the particle counts. It is noted that impurity Mg has a more significant effect than Na in crystal growth of the whole crystallization process. From the microscopic observation of crystals, Mg has an obvious effect on the crystal habit, while Na has little effect. In addition, the crystal habit changes can be monitored by particle vision measurement (PVM). Understanding these effects is helpful to aid optimization and improve process control.

关键词: cobalamin     impurity     particle     addition     technique    

Effect of 2,5-dimethylfuran addition on ignition delay times of n-heptane at high temperatures

Zhenhua GAO, Erjiang HU, Zhaohua XU, Geyuan YIN, Zuohua HUANG

《能源前沿(英文)》 2019年 第13卷 第3期   页码 464-473 doi: 10.1007/s11708-019-0609-z

摘要: The shock tube autoignition of 2,5-dimethylfuran (DMF)/n-heptane blends (DMF0-100%, by mole fraction) with equivalence ratios of 0.5, 1.0, and 2.0 over the temperature range of 1200–1800 K and pressures of 2.0 atm and 10.0 atm were investigated. A detailed blend chemical kinetic model resulting from the merging of validated kinetic models for the components of the fuel blends was developed. The experimental observations indicate that the ignition delay times nonlinearly increase with an increase in the DMF addition level. Chemical kinetic analysis including radical pool analysis and flux analysis were conducted to explain the DMF addition effects. The kinetic analysis shows that at lower DMF blending levels, the two fuels have negligible impacts on the consumption pathways of each other. As the DMF addition increases to relatively higher levels, the consumption path of n-heptane is significantly changed due to the competition of small radicals, which primarily leads to the nonlinear increase in the ignition delay times of DMF/n-heptane blends.

关键词: ignition delay time     shock tube     kinetic model     2     5-dimethylfuran (DMF)     n-heptane    

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    

Effect of the addition of organic carbon sources on nitrous oxide emission in anaerobic-aerobic (low

Hongjing LI, Xiurong CHEN, Yinguang CHEN

《环境科学与工程前沿(英文)》 2010年 第4卷 第4期   页码 490-499 doi: 10.1007/s11783-010-0248-4

摘要: The effect of additional organic carbon sources on the production of nitrous oxide (N O) in anaerobic-aerobic (low dissolved oxygen) real wastewater treatment system was investigated. In this paper, three laboratory-scale sequencing batch reactors (SBRs) (SBR-1, SBR-2 and SBR-3) were operating under an anaerobic-aerobic (low dissolved oxygen, 0.15–0.45 mg·L ) configuration. The SBRs were ‘long-term cultured’ respectively with a single municipal wastewater sample, sodium acetate, and a waste-activated sludge alkaline fermentation liquid as the additional carbon sources of real wastewater. Off-gas analysis showed that N O was emitted into the atmosphere during the aerobic (low dissolved oxygen) period in the three SBRs, and the order of N O emission rate was SBR-2>SBR-1>SBR-3. It was observed that the higher poly-β-hydroxyvalerate fraction of polyhydroxyalkanoates, the lower glycogen transformation and less nitrite accumulation was in SBR-3, while the opposite behavior was observed in SBR-2. Further research indicated that the interaction of the factors above potentially affected the N O emission in the anaerobic-aerobic (low dissolved oxygen) system.

关键词: anaerobic-aerobic (low dissolved oxygen)     nitrous oxide (N2O) emitting rate     municipal wastewater     waste activated sludge     alkaline fermentation liquid    

N-Positive ion activated rapid addition and mitochondrial targeting ratiometric fluorescent probes

Yan Shi, Fangjun Huo, Yongkang Yue, Caixia Yin

《化学科学与工程前沿(英文)》 2022年 第16卷 第1期   页码 64-71 doi: 10.1007/s11705-021-2048-8

摘要: Heterocyclic compound quinoline and its derivatives exist in natural compounds and have a broad spectrum of biological activity. They play an important role in the design of new structural entities for medical applications. Similarly, indoles and their derivatives are found widely in nature. Amino acids, alkaloids and auxin are all derivatives of indoles, as are dyes, and their condensation with aldehydes makes it easy to construct reaction sites for nucleophilic addition agents. In this work, we combine these two groups organically to construct a rapid response site (within 30 s) for H S, and at the same time, a ratiometric fluorescence response is presented throughout the process of H S detection. As such, the lower detection limit can reach 55.7 nmol/L for H S. In addition, cell imaging shows that this probe can be used for the mitochondrial targeted detection of endogenous and exogenous H S. Finally, this probe application was verified by imaging H S in nude mice.

关键词: heterocyclic compound     hydrogen sulfide     ratiometric     mitochondrial targeted    

Sludge fermentation liquid addition attained advanced nitrogen removal in low C/N ratio municipal wastewater

Shengjie Qiu, Jinjin Liu, Liang Zhang, Qiong 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/s11783-020-1318-x

摘要: Abstract • Sludge fermentation liquid addition resulted in a high NAR of 97.4%. • Extra NH4+-N from SFL was removed by anammox in anoxic phase. • Nitrogen removal efficiency of 92.51% was achieved in municipal wastewater. • The novel system could efficiently treat low COD/N municipal wastewater. Biological nitrogen removal of wastewater with low COD/N ratio could be enhanced by the addition of wasted sludge fermentation liquid (SFL), but the performance is usually limited by the introducing ammonium. In this study, the process of using SFL was successfully improved by involving anammox process. Real municipal wastewater with a low C/N ratio of 2.8–3.4 was treated in a sequencing batch reactor (SBR). The SBR was operated under anaerobic-aerobic-anoxic (AOA) mode and excess SFL was added into the anoxic phase. Stable short-cut nitrification was achieved after 46d and then anammox sludge was inoculated. In the stable period, effluent total inorganic nitrogen (TIN) was less than 4.3 mg/L with removal efficiency of 92.3%. Further analysis suggests that anammox bacteria, mainly affiliated with Candidatus_Kuenenia, successfully reduced the external ammonia from the SFL and contributed approximately 28%–43% to TIN removal. Overall, this study suggests anammox could be combined with SFL addition, resulting in a stable enhanced nitrogen biological removal.

关键词: Sludge fermentation liquid     Municipal wastewater     Advanced nitrogen removal     Short-cut nitrification     Partial anammox    

Metabolic uncoupler, 3,3′,4′,5-tetrachlorosalicylanilide addition for sludge reduction and fouling control

An Ding, Yingxue Zhao, Huu Hao Ngo, Langming Bai, Guibai Li, Heng Liang, Nanqi Ren, Jun Nan

《环境科学与工程前沿(英文)》 2020年 第14卷 第6期 doi: 10.1007/s11783-020-1275-4

摘要: Abstract • Effects of metabolic uncoupler TCS on the performances of GDMBR were evaluated. • Sludge EPS reduced and transformed into dissolved SMP when TCS was added. • Appropriate TCS increased the permeability and reduced cake layer fouling. • High dosage aggravated fouling due to compact cake layer with low bio-activity. The gravity-driven membrane bioreactor (MBR)system is promising for decentralized sewage treatment because of its low energy consumption and maintenance requirements. However, the growing sludge not only increases membrane fouling, but also augments operational complexities (sludge discharge). We added the metabolic uncoupler 3,3′,4′,5-tetrachlorosalicylanilide (TCS) to the system to deal with the mentioned issues. Based on the results, TCS addition effectively decreased sludge ATP and sludge yield (reduced by 50%). Extracellular polymeric substances (EPS; proteins and polysaccharides) decreased with the addition of TCS and were transformed into dissolved soluble microbial products (SMPs) in the bulk solution, leading to the break of sludge flocs into small fragments. Permeability was increased by more than two times, reaching 60–70 L/m2/h bar when 10–30 mg/L TCS were added, because of the reduced suspended sludge and the formation of a thin cake layer with low EPS levels. Resistance analyses confirmed that appropriate dosages of TCS primarily decreased the cake layer and hydraulically reversible resistances. Permeability decreased at high dosage (50 mg/L) due to the release of excess sludge fragments and SMP into the supernatant, with a thin but more compact fouling layer with low bioactivity developing on the membrane surface, causing higher cake layer and pore blocking resistances. Our study provides a fundamental understanding of how a metabolic uncoupler affects the sludge and bio-fouling layers at different dosages, with practical relevance for in situ sludge reduction and membrane fouling alleviation in MBR systems.

关键词: Gravity-driven membrane (GDM)     Energy uncoupling     Permeability     Sludge reduction     Membrane fouling     Fouling layer    

Chaotic behavior of LNG after stratification in main stream region of storage tank

WANG Jingjing, MA Xiaoqian

《能源前沿(英文)》 2008年 第2卷 第4期   页码 514-518 doi: 10.1007/s11708-008-0076-4

摘要: A study of the chaotic behavior of liquefied natural gas (LNG) after stratification in the main stream region of a storage tank was conducted. Based on non-linear dynamics, a 2-dimensional Rayleigh-Benard convection model was developed to simulate the convection, Lorenz equations of LNG convection were deduced from conservation equations, and the Runge-Kutta method was used to solve the equations. The results showed that when = 1.33, 106 < < 1470, chaos was obtained, which meant that the velocity field and the temperature field were highly unsteady. In addition, the influence of temperature and scale factor on the solutions and the corresponding range of parameters were studied. The results revealed that the chaos in LNG convection resulted from the interaction of buoyancy and viscid forces. A small quantity of heat impacting the storage tank would lead to a strong and unstable convection of LNG in the main stream region.

关键词: Runge-Kutta     non-linear     corresponding     temperature     addition    

Analysis of behavior of melted dark green silty soil

TANG Yiqun, ZHOU Nianqing, YANG Ping, SHEN Feng

《结构与土木工程前沿(英文)》 2008年 第2卷 第3期   页码 242-245 doi: 10.1007/s11709-008-0022-x

摘要: The behavior of dark green silty soil of the 6th storey is studied by means of scanning electron microscopy (SEM). The shape, size and contact condition of the basic elements of the soil microstructure, and the shape and the size of the pore are further studied. In addition, a comparative study is made to analyze the experiment results of Cu and dynamic test. The mechanic characteristics of common soil and those of melted soil are presented and their influences on dark silty soil after being frozen are theoretically illustrated from a microscopic perspective.

关键词: electron microscopy     mechanic     microscopic perspective     addition     dynamic    

标题 作者 时间 类型 操作

Sinks of steel in China–addition to in-use stock, export and loss

Hua GUO,Tianzhu ZHANG

期刊论文

Effect of short-term atrazine addition on the performance of an anaerobic/anoxic/oxic process

Changyong WU, Xiaoling LI, Zhiqiang CHEN, Yongzhen PENG,

期刊论文

Hydration, microstructure and autogenous shrinkage behaviors of cement mortars by addition of superabsorbent

Beibei SUN, Hao WU, Weimin SONG, Zhe LI, Jia YU

期刊论文

Mass loss and nutrient dynamics during litter decomposition in response to warming and nitrogen addition

Haiyan REN, Jie QIN, Baolong YAN, Alata, Baoyinhexige, Guodong HAN

期刊论文

Carbon-coated lithium titanate: effect of carbon precursor addition processes on the electrochemical

Shilei Ding, Zelong Jiang, Jing Gu, Hongliang Zhang, Jiajia Cai, Dongdong Wang

期刊论文

基于强化模糊认知图实现数据与知识协作的氟化铝添加量决策方法

岳伟超, 桂卫华, 陈晓方, 曾朝晖, 谢永芳

期刊论文

Effects of ionic impurities on crystallization of cobalamin

Baoli SHAO, Hui CHEN, Shuang WANG, Haijun WANG, Shenmin XU,

期刊论文

Effect of 2,5-dimethylfuran addition on ignition delay times of n-heptane at high temperatures

Zhenhua GAO, Erjiang HU, Zhaohua XU, Geyuan YIN, Zuohua HUANG

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

Effect of the addition of organic carbon sources on nitrous oxide emission in anaerobic-aerobic (low

Hongjing LI, Xiurong CHEN, Yinguang CHEN

期刊论文

N-Positive ion activated rapid addition and mitochondrial targeting ratiometric fluorescent probes

Yan Shi, Fangjun Huo, Yongkang Yue, Caixia Yin

期刊论文

Sludge fermentation liquid addition attained advanced nitrogen removal in low C/N ratio municipal wastewater

Shengjie Qiu, Jinjin Liu, Liang Zhang, Qiong Zhang, Yongzhen Peng

期刊论文

Metabolic uncoupler, 3,3′,4′,5-tetrachlorosalicylanilide addition for sludge reduction and fouling control

An Ding, Yingxue Zhao, Huu Hao Ngo, Langming Bai, Guibai Li, Heng Liang, Nanqi Ren, Jun Nan

期刊论文

Chaotic behavior of LNG after stratification in main stream region of storage tank

WANG Jingjing, MA Xiaoqian

期刊论文

Analysis of behavior of melted dark green silty soil

TANG Yiqun, ZHOU Nianqing, YANG Ping, SHEN Feng

期刊论文