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Synergistic promotion of particulate matter reduction and production performance via adjusting electrochemical reactions in the zinc electrolysis industry

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Frontiers of Environmental Science & Engineering 2024年第1期18卷 23-33页

作者： Zizhen Ma Jingkun Jiang Lei duan Jianguo Deng Fuyuan Xu Zehui Li Linhua Jiang ning duan School of Environmental and Municipal Engineering Qingdao University of TechnologyQingdao 266520China State Key Joint Laboratory of Environmental Simulation and Pollution Control School of the EnvironmentTsinghua UniversityBeijing 100084China State Key Laboratory of Pollution Control and Resources Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China School of Physics Peking UniversityBeijing 100871China

Heavy particulate matter (PM) pollution and high energy consumption are the bottlenecks of hydrometallurgy, especially in the electrolysis process. Therefore, an urgent need is to explore PM reduction methods with production performance co-benefits. This study presents three PM reduction methods based on controlling operating parameters, i.e., lowering electrolyte temperature, H2SO4 concentration, and current density of the cathode. The optimized conditions were also investigated using the response surface methodology to balance the PM reduction effect and Zn production. The results showed that lowering electrolyte temperature is the most efficient, with an 89.0% reduction in the PM generation flux (GFPM). Reducing H2SO4 concentration led to the minimum side effects on the current efficiency of Zn deposition (CEZn) or power consumption (PC). With the premise of non-deteriorating CEZn and PC, GFPM can be reduced by 86.3% at the optimal condition (electrolyte temperature = 295 K, H2SO4 = 110 g/L, current density = 373 A/m^(2)). In addition, the reduction mechanism was elucidated by comprehensively analyzing bubble characteristics, electrochemical reactions, and surface tension. Results showed that lower electrolyte temperature inhibited the oxygen evolution reaction (OER) and compressed gas volume. Lower H2SO4 concentration inhibited the hydrogen evolution reaction (HER) and reduced electrolyte surface tension. Lower current density inhibited both OER and HER by decreasing the reaction current. The inhibited gas evolutions reduced the microbubbles’ number and size, thereby reducing GFPM. These results may provide energy-efficient PM reduction methods and theoretical hints of exploring cleaner PM reduction approaches for industrial electrolysis.

关键词： Zinc electrolysis Particulate matter Energy consumption Operating parameters Bubble characteristic Electrochemical reaction

Interfacial reinforcement of core-shell HMX@energetic polymer composites featuring enhanced thermal and safety performance

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Defence Technology（防务技术） 2024年第1期31卷 387-399页

作者： Binghui duan Hongchang Mo Bojun Tan Xianming Lu Bozhou Wang ning Liu Xi'an Modern Chemistry Research Institute Xi'an710065People's Republic of China State Key Laboratory of Fluorine&Nitrogen Chemicals Xi'an710065People's Republic of China

The weak interface interaction and solid-solid phase transition have long been a conundrum for 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane(HMX)-based polymer-bonded explosives(PBX).A two-step strategy that involves the pretreatment of HMX to endow—OH groups on the surface via polyalcohol bonding agent modification and in situ coating with nitrate ester-containing polymer,was proposed to address the *** types of energetic polyether—glycidyl azide polymer(GAP)and nitrate modified GAP(GNP)were grafted onto HMX crystal based on isocyanate addition reaction bridged through neutral polymeric bonding agent(NPBA)*** morphology and structure of the HMX-based composites were characterized in detail and the core-shell structure was *** grafted polymers obviously enhanced the adhesion force between HMX crystals and fluoropolymer(F2314)*** to the interfacial reinforcement among the components,the two HMX-based composites exhibited a remarkable increment of phase transition peak temperature by 10.2°C and 19.6°C with no more than 1.5%shell content,***,the impact and friction sensitivity of the composites decreased significantly as a result of the barrier produced by the grafted *** findings will enhance the future prospects for the interface design of energetic composites aiming to solve the weak interface and safety concerns.

关键词： HMX crystals Polyalcohol bonding agent Energetic polymer Core-shell structure Interfacial reinforcement

Umbilical cord mesenchymal stem cell exosomes alleviate necrotizing enterocolitis in neonatal mice by regulating intestinal epithelial cells autophagy

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World Journal of Stem Cells 2024年第6期16卷 728-738页

作者： Lin Zhu Lu He Wu duan Bo Yang ning Li Department of Pediatrics Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430077Hubei ProvinceChina Division of Endocrinology Department of Internal MedicineQilu Hospital of Shandong UniversityJinan 250012Shandong ProvinceChina Shenzhen Research Institute of Shandong University Shenzhen 518000Guangdong ProvinceChina Institute of Organ Transplantation Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430077Hubei ProvinceChina Department of Physical Education Heze UniversityHeze 274015Shandong ProvinceChina

BACKGROUND Necrotizing enterocolitis(NEC)is a severe gastrointestinal disease that affects premature *** mounting evidence supports the therapeutic effect of exosomes on NEC,the underlying mechanisms remain *** To investigate the mechanisms underlying the regulation of inflammatory response and intestinal barrier function by umbilical cord mesenchymal stem cell(UCMSCs)exosomes,as well as their potential in alleviating NEC in neonatal *** NEC was induced in 5-d-old C57BL/6 pups through hypoxia and gavage feeding of formula containing lipopolysaccharide(LPS),after which the mice received human UCMSC exosomes(hUCMSC-exos).The control mice were allowed to breastfeed with their *** tissues were collected from the mice and analyzed by histopathology and *** tissues were collected from NEC neonates and analyzed by *** biology and cell culture approaches were employed to study the related mechanisms in intestinal epithelial *** We found that autophagy is overactivated in intestinal epithelial cells during NEC,resulting in reduced expression of tight junction proteins and an increased inflammatory *** ability of hUCMSC-exos to ameliorate NEC in a mouse model was dependent on decreased intestinal *** also showed that hUCMSC-exos alleviate the inflammatory response and increase migration ability in intestinal epithelial cells induced by *** These results contribute to a better understanding of the protective mechanisms of hUCMSC-exos against NEC and provide a new theoretical and experimental foundation for NEC *** findings also enhance our understanding of the role of the autophagy mechanism in NEC,offering potential avenues for identifying new therapeutic targets.

关键词： Necrotizing enterocolitis Autophagy Umbilical cord mesenchymal stem cell Exosomes Intestinal epithelial cell Intestinal barrier function

Low-temperature NH_(3)-SCR performance of a novel Chlorella@Mn composite denitrification catalyst

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Journal of Environmental Sciences 2024年第3期137卷 271-286页

作者： Hengheng Liu Fengyu Gao Songjin Ko ning Luo Xiaolong Tang Erhong duan Honghong Yi Yuansong Zhou School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants Beijing 100083China School of Environmental Science and Engineering University of Science and Technology HebeiHebei 050018China Department of Chemistry Pyongyang University of ArchitecturePyongyangDemocratic People’s Republic of Korea

The synthesis process of conventional Mn-based denitrification catalysts is relatively complex and *** this paper,a resource application of chlorella was proposed,and a Chlorella@Mn composite denitrification catalyst was innovatively synthesized by electrostatic *** Chlorella@Mn composite denitrification catalyst prepared under the optimal conditions(0.54 g/L Mn^(2+)concentration,20 million chlorellas/mL concentration,450℃ calcination temperature)exhibited a well-developed pore structure and large specific surface area(122 m^(2)/g).Compared with MnOx alone,the Chlorella@Mn composite catalyst achieved superior performance,with~100%NH_(3)selective catalytic reduction(NH_(3)-SCR)denitrification activity at 100-225℃.The results of NH_(3)temperature-programmed desorption(NH_(3)-TPD)and H_(2)temperature-programmed reduction(H_(2)-TPR)showed that the catalyst had strong acid sites and good redox *** potential testing showed that the electronegativity of the chlorella cell surface could be used to enrich with Mn^(2+).X-ray photoelectron spectroscopy(XPS)confirmed that Chlorella@Mn had a high content of Mn^(3+)and surface chemisorbed ***-situ diffuse refectance infrared Fourier transform spectroscopy(in-situ DRIFTS)experimental results showed that both Langmuir-Hinshelwood(L-H)and Eley-Rideal(E-R)mechanisms play a role in the denitrification process on the surface of the Chlorella@Mn catalyst,where the main intermediate nitrate species is monodentate *** presence of SO_(2)promoted the generation and strengthening of Bronsted acid sites,but also generated more sulfate species on the surface,thereby reducing the denitrification activity of the Chlorella@Mn *** Chlorella@Mn composite catalyst had the characteristics of short preparation time,simple process and low cost,making it promising for industrial application.

关键词： Chlorella@Mn catalyst NH_(3)-SCR Poisoning resistance Reaction mechanism Infuence of SO_(2)

Rheological behavior and constitutive equations of heterogeneous titanium-bearing molten slag

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International Journal of Minerals,Metallurgy and Materials 2015年第8期22卷 804-810页

作者： Tao Jiang De-ming Liao Mi Zhou Qiao-yi Zhang Hong-rui Yue Song-tao Yang pei-ning duan Xiang-xin Xue School of Materials and Metallurgy Northeastern University Liaoning Key Laboratory for Recycling Science of Metallurgical Resources

Experimental studies on the rheological properties of a Ca O–Si O2–Al2O3–Mg O–Ti O2–(Ti C) blast furnace(BF) slag system were conducted using a high-temperature rheometer to reveal the non-Newtonian behavior of heterogeneous titanium-bearing molten slag. By measuring the relationships among the viscosity, the shear stress and the shear rate of molten slags with different Ti C contents at different temperatures, the rheological constitutive equations were established along with the rheological parameters; in addition, the non-Newtonian fluid types of the molten slags were determined. The results indicated that, with increasing Ti C content, the viscosity of the molten slag tended to increase. If the Ti C content was less than 2wt%, the molten slag exhibited the Newtonian fluid behavior when the temperature was higher than the critical viscosity temperature of the molten slag. In contrast, the molten slag exhibited the non-Newtonian pseudoplastic fluid characteristic and the shear thinning behavior when the temperature was less than the critical viscosity temperature. However, if the Ti C content exceeded 4wt%, the molten slag produced the yield stress and exhibited the Bingham and plastic pseudoplastic fluid behaviors when the temperature was higher and lower than the critical viscosity temperature, respectively. When the Ti C content increased further, the yield stress of the molten slag increased and the shear thinning phenomenon became more obvious.

关键词： molten slag rheological behavior constitutive equa

High-Speed Rubbing Behavior of Abrasive Coating Coated on Titanium Alloy Blade Tips

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 749-762页

作者： Wenshuang Gu Shuai Yang Shiyi Zhang Zhiliang pei Weihai Xue Deli duan Jun Gong Chao Sun Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China

In aero-engines, abrasive coatings are typically utilized to protect the blade tip from excessive wear caused by the harder abradable sealing coating and thereby improve the sealing performance of engines. Therefore, a Ni/cBN abrasive coating was prepared on titanium alloy using electrodeposition. The high-speed rubbing tests with a linear velocity of 350 m/s and different incursion rates were performed to investigate the effect of the Ni/cBN abrasive coating on the wear behavior against NiCrAl/diatomite seal coating. Results showed that melting wear and adhesive transfer occurred on the bare blades, causing the bare blade to suffer excessive wear. While the Ni/cBN abrasive coating exhibited superior wear resistance and cutting performance. The cBN grits pullout, the abrasion of Ni matrix and transfer of seal coating to the cBN grits were the main wear mechanism of the Ni/cBN abrasive coating. Additionally, it was found that the relationship between the incursion rate and high-speed rubbing behavior is quite different for the bare blade and Ni/cBN coating. The reason for the difference in wear behavior of bare blade and Ni/cBN coating at different incursion rates was discussed in detail.

关键词： Gas turbine sealing Abrasive coating High-speed rubbing Material transfer Abradable coating

Direct generation of Zn metal using laser-induced ZnS to eradicate carbon emissions from electrolysis Zn production

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Frontiers of Environmental Science & Engineering 2024年第1期18卷 83-95页

作者： Ying Chen ning duan Linhua Jiang Fuyuan Xu Guangbin Zhu Yao Wang Yong Liu Wen Cheng Yanli Xu State Key Laboratory of Pollution Control and Resources Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China School of Environmental Science and Engineering Tianjin UniversityTianjin 300350China School of Materials Science and Engineering Anhui University of Science&TechnologyHuainan 232001China

In response to the goal of net-zero emissions proposed by Intergovernmental Panel on Climate Change, Chinese government has pledged that carbon emissions will peak by 2030, and achieve carbon neutrality by 2060. However, the high carbon energy structure of traditional industries has aggravated environmental problems, such as greenhouse effect and air pollution. The goal of carbon neutrality will be difficult to achieve without the development of disruptive theories and technologies. The electrolytic zinc industry requires high-temperature roasting at ~1000 ℃, generating large amounts of greenhouse gases and SO_(2). High concentrations of sulfuric acid (200 g/L) are subsequently used for electrolysis, and each ton of zinc produced generates 50 kg of anode slime with lead content of up to 16%, as well as 0.35 m3 of wastewater containing zinc and lead. To solve these problems, an optical metallurgy method is proposed in this study. The proposed method uses laser-induced photoreduction to decompose ZnS and reduce metal ions to metal. Results indicate that Zn0 and S8 can be detected on the surface of ZnS at a specific wavelength and laser fluence. The generation mechanism of Zn0 is such that laser induces an electronic transition that breaks ionic bond in ZnS, resulting in its decomposition and photoreduction to Zn0 under an inert argon gas atmosphere. This method does not reduce other metals in the mineral since it does not use high-temperature roasting, providing a new way of producing high-purity metal without greenhouse gas emissions and heavy metal pollution caused by traditional zinc electrolysis.

关键词： Laser metallurgy ZnS Photochemical reduction Zinc

Development of a Front End Array for Broadband Phased Array Receiver

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Research in Astronomy and Astrophysics 2024年第4期24卷 60-70页

作者： Kai Wang Liang Cao Jun Ma Xue-Feng duan Hao Yan Mao-Zheng Chen Yun-Wei ning Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 8300lChina University of the Chinese Academy of Sciences Beijing 100049China Xinjiang Key Laboratory of Microwave Technology Urumqi 830011China

The receiver is a signal receiving device placed at the focus of the *** order to improve the observation efficiency,the concept of phased array receiver has been proposed in recent years,which places a small phased array at the focal plane of the reflector,and flexible pattern and beam scanning functions can be achieved through a beamforming *** combined with the element multiplexing,all beams within the entire field of view can be observed simultaneously to achieve continuous sky *** article focuses on the front-end array of phased array receiver at 0.7-1.8 GHz for QiTai Telescope,and designs a Vivaldi antenna array of PCB structure with dual line *** polarization antenna is designed to arrange in a rectangle manner by 11×*** on the simulation results of the focal field,32,18,and eight elements were selected to form one beam at 0.7,1.25,and1.8 *** analog beamforming network was constructed,and the measured gains of axial beam under uniform weighting were 19.32,13.72,and 15.22 *** the beam scanning method of reflector antenna,the pattern test of different position element sets required for PAF beam scanning was carried out under independent *** pattern optimization at 1.25 GHz was carried out by weighting method of conjugate field *** with uniform weighting,the gain,sidelobe level,and main beam direction under conjugate field matching have been *** the above test and simulation results are slightly different,which is related to the passive array and laboratory testing condition,the relevant work has accumulated experience in the development of the front-end array for the phased array receiver,and has good guiding significance for future performance verification after the array is installed on the telescope.

关键词： telescopes instrumentation:detectors techniques:radar astronomy

Carbon dots-derived three-dimensional-ordered macroporous host with high penetrability and catalytic activity for LSBs under lean electrolyte

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Rare Metals 2024年第6期43卷 2560-2573页

作者： Jiao-Zi duan Hua-Yu pei Quan Yang Xue Li Xin Ba Xue Yong Jun-Ling Guo Si-Yu Lu Green Catalysis Center College of ChemistryZhengzhou UniversityZhengzhou 450001China Country State Center for International Cooperation On Designer Low-Carbon&Environmental Materials School of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001China Hubei Institute of Quality Supervision Inspection Wuhan 430061China Department of Chemistry University of SheffieldSheffeld S37HFUK

The practical energy density of lithium-sulfur batteries(LSBs)is seriously limited by the high electrolyte-to-sulfur ratios(E/S).The E/S can be reduced by employing hosts with easy-to-infiltrate structure that ensures the uniform distribution of a lean electrolyte and high catalytic activity that can suppress"shuttle effect"via accelerating the slow conversion of soluble poly sulfides to insoluble *** the easy-to-infiltrate structures,the three-dimensional-ordered macroporous(3DOM)structure is easier to scale preparation and more suitable for the existing industrial ***,it is difficult to obtain the 3DOM with(1)high penetrability due to the high viscosity of frequently-used organic polymer precursors and(2)high catalytic activity due to the low confinement effect,meaning that uniformly dispersed small-sized catalytic materials are difficult to load on ***,using carbon dots(CDs)with both organic and inorganic properties as a precursor and aggregation limiting agent,a 3DOM host with high penetrability and homodispersed Ni particles of small sizes(Ni-CDs-3DOM)was *** this host:(1)CDs precursor with suitable viscosity can improve the penetrability.(2)CDs can effectively inhibit the agglomeration of Ni particles.(3)Uniformly dispersed small-size Ni particles offer high-efficiency catalytic activity toward sulfur ***,the Ni-CDs-3DOM/sulfur cathode exhibits high sulfur utilization and stable cycling performance even under high sulfur loading(5.5 mg·cm^(-2))and low E/S(6.5μl·mg^(-1)).This work indicates the usefulness of CDs in constructing hosts for LSBs with high energy density.

关键词： Lithium-sulfur batteries Carbon dots Catalytic action Easy-to-infiltrate structure Lean electrolyte