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Microstructure and impact behavior of Mg-4Al-5RE-xGd cast magnesium alloys

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Journal of Magnesium and Alloys 2024年第5期12卷 1799-1814页

作者： Jie Wei Qudong Wang huisheng Cai Mahmoud Ebrahimi Chuan lei National Engineering Research Center of light Alloy Net Forming and Key State laboratory of Metal Matrix Composites School of Materials Science and Engineering Shanghai Jiao Tong University

This work investigated the microstructure and impact behavior of Mg-4Al-5RE-xGd（RE represents la-Ce mischmetal; x = 0, 0.2,0.7 wt.%） alloys cast by high-pressure die casting（HPDC）, permanent mold casting（PMC）, and sand casting（SC） techniques. The results indicated that with increasing Gd content, the grain sizes of the HPDC alloy had a slight change, but the grains of the PMC and SC alloys were significantly refined. Besides, the acicular Al11RE3phase was modified into the short-rod shape under the three casting conditions. The impact toughness of the studied alloy was mainly dominated by the absorbed energy during the crack initiation. With increasing Gd content,the impact toughness of the studied alloy monotonically increased due to the lower tendency of the modified second phase toward crack initiation. The impact stress was higher than the tensile stress, exhibiting a strain rate sensitivity for the mechanical response; however, the HPDC alloy had an inconsistent strain rate sensitivity during the impact event due to the transformation of the deformation mechanism from twinning to slip with increasing strain. Abundant dimples covered the fracture surface of the fine-grained HPDC alloys, indicating a typical ductile fracture. Nevertheless, due to the deficient {■} twinning activity and the suppressed grain boundary sliding during the impact event, the HPDC alloys showed insufficient plastic deformation capacity.

关键词： Mg-Al-RE alloy Gadolinium Microstructure Impact behavior

Flexible electrochemical fiber sensor for intracranial nitric oxide monitoring

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Science China Chemistry 2024年第8期 2431-2433页

作者： Ziwei liu huisheng Peng State Key laboratory of Molecular Engineering of Polymers Department of Macromolecular Science Institute of Fiber Materials and Devices and Laboratory of Advanced Materials Fudan University

Real-time and accurate monitoring of vital biomarkers in vivo forms a crucial foundation for health assessment, early intervention, and disease treatment. Specifically, continuous monitoring of intracranial nitric oxide (NO) levels plays a pivotal role in promptly assessing immune responses, neurovirulence, and cerebrovascular diseases [1]. Differing from non-real-time monitoring methods like chemiluminescence [2] and fluorescent probes [3], implantable electrochemical sensors excel in simultaneously high temporal resolution,sensitivity, and cost-effectiveness [4].

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Calcium carbonate promotes the formation and stability of soil macroaggregates in mining areas of China

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Journal of Integrative Agriculture 2024年第3期23卷 1034-1047页

作者： Junyu Xie Jianyong Gao Hanbing Cao Jiahui li Xiang Wang Jie Zhang huisheng Meng Jianping Hong Tingliang li Minggang Xu College of Resources and Environment Shanxi Agricultural UniversityTaigu 030801China Shanxi Province Key laboratory of Soil Environment and Nutrient Resources Taiyuan 030031China College of land Science and Technology China Agricultural UniversityBeijing 100193China

We studied changes in the concentrations of aggregate-cementing agents after different reclamation times and with different fertilization regimes,as well as the formation mechanism of aggregates in reclaimed soil,to provide a theoretical basis for rapid reclamation of soil fertility in the subsidence area of coal mines in Shanxi Province,China.In this study,soil samples of 0–20 cm depth were collected from four fertilization treatments of a longterm experiment started in 2008:no fertilizer (CK),inorganic fertilizer (NPK),chicken manure compost (M),and50%inorganic fertilizer plus 50%chicken manure compost (MNPK).The concentrations of cementing agents and changes in soil aggregate size distribution and stability were analysed.The results showed that the formation of>2 mm aggregates,the aggregate mean weight diameter (MWD),and the proportion of>0.25 mm water-stable aggregates (WR_(0.25)) increased significantly after 6 and 11 years of reclamation.The concentration of organic cementing agents tended to increase with reclamation time,whereas free iron oxide (Fed) and free aluminium oxide(Ald) concentrations initially increased but then decreased.In general,the MNPK treatment signi?cantly increased the concentrations of organic cementing agents and CaCO_(3),and CaCO_(3) increased by 60.4%at 11 years after reclamation.Additionally,CaCO_(3) had the greatest effect on the stability of aggregates,promoting the formation of>0.25 mm aggregates and accounting for 54.4%of the variance in the proportion and stability of the aggregates.It was concluded that long-term reclamation is bene?cial for improving soil structure.The MNPK treatment was the most effective measure for increasing maize grain yield and concentration of organic cementing agents and CaCO_(3).

关键词： reclamation time manure combined with inorganic fertilizer soil aggregate stability cementing agents CaCO_(3)

史前考古学文化的演变与嬗变——以青海宗日遗址为中心

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齐鲁学刊 2024年第3期 38-58页

作者：汤惠生河北师范大学历史文化学院河北石家庄050024

青海省海南州宗日遗址包含有新石器时代晚期的宗日文化、马家窑文化和青铜时代的齐家文化、卡约文化。这几种考古学文化在宗日遗址上展示出演变、进化和嬗变三种文明的起源与发展模式,为我们了解考古学文化的进程提供了丰富而生动的第... 详细信息

青海省海南州宗日遗址包含有新石器时代晚期的宗日文化、马家窑文化和青铜时代的齐家文化、卡约文化。这几种考古学文化在宗日遗址上展示出演变、进化和嬗变三种文明的起源与发展模式,为我们了解考古学文化的进程提供了丰富而生动的第一手资料。宗日文化、马家窑文化和齐家文化之间的关系由于都是以农业为主导的定居文化,所以呈现出碰撞、融汇和适应的包容关系;而卡约文化替续齐家文化时,由于完全不同的经济模式、生活方式以及社会形态,故显示出暴力的对抗和革命的关系。

关键词：青海史前考古学文化宗日文化马家窑文化齐家文化卡约文化演变与嬗变藏彝走廊

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FGF7 enhances the expression of ACE2 in human islet organoids aggravating SARS-CoV-2 infection

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Signal Transduction and Targeted Therapy 2024年第5期9卷 2260-2274页

作者： Hao Meng Zhiying liao Yanting Ji Dong Wang Yang Han Chaolin Huang Xujuan Hu Jingyi Chen Hengrui Zhang Zonghong li Changliang Wang Hui Sun Jiaqi Sun lihua Chen Jiaxiang Yin Jincun Zhao Tao Xu huisheng liu School of Biomedical Engineering Guangzhou Medical UniversityGuangzhou 511495 GuangdongChina Guangzhou National laboratory Guangzhou 510320 GuangdongChina State Key laboratory of Respiratory Disease National Clinical Research Center for Respiratory DiseaseGuangzhou Institute of Respiratory HealthThe First Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510120China Center for Translational Medicine Wuhan Jinyintan HospitalWuhan 430023 HubeiChina School of Biomedical Sciences and Engineering South China University of TechnologyGuangzhou 510006 GuangdongChina

The angiotensin-converting enzyme 2(ACE2)is a primary cell surface viral binding receptor for SARS-CoV-2,so finding new regulatory molecules to modulate ACE2 expression levels is a promising strategy against COVID-19.In the current study,we utilized islet organoids derived from human embryonic stem cells(hESCs),animal models and COVID-19 patients to discover that fibroblast growth factor 7(FGF7)enhances ACE2 expression within the islets,facilitating SARS-CoV-2 infection and resulting in impaired insulin secretion.Using hESC-derived islet organoids,we demonstrated that FGF7 interacts with FGF receptor 2(FGFR2)and FGFR1 to upregulate ACE2 expression predominantly inβcells.This upregulation increases both insulin secretion and susceptibility ofβcells to SARS-CoV-2 infection.Inhibiting FGFR counteracts the FGF7-induced ACE2 upregulation,subsequently reducing viral infection and replication in the islets.Furthermore,retrospective clinical data revealed that diabetic patients with severe COVID-19 symptoms exhibited elevated serum FGF7 levels compared to those with mild symptoms.Finally,animal experiments indicated that SARS-CoV-2 infection increased pancreatic FGF7 levels,resulting in a reduction of insulin concentrations in situ.Taken together,our research offers a potential regulatory strategy for ACE2 by controlling FGF7,thereby protecting islets from SARS-CoV-2 infection and preventing the progression of diabetes in the context of COVID-19.

关键词： ACE2 FGF7 islet

Optimization of hydrothermal pretreatment for co-utilization of xylose and glucose of cassava anaerobic residue for producing ethanol

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Chinese Journal of Chemical Engineering 2019年第4期27卷 920-927页

作者： huisheng lü Jinyi Zhou Jiatao liu Chunliu lü Feng lian Yonghui li Key laboratory for Green Chemical Technology of Ministry of Education R&D Center for Petrochemical Technology Tianjin University Tianjin 300072 China Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300072 China

The development of a process that could recover biofuel from industrial cellulose waste can not only reduce the negative environmental impacts by using fossil fuels, but also bring a green idea for the waste’s disposing. In this study, hydrothermal pretreatment was optimized for cassava anaerobic residue, a cellulosic waste from cassava ethanol industry, to co-utilize xylose and glucose for producing bioethanol. The effect of the main pretreatment conditions, namely, temperature, solid content and time, was explored for the highest recovery of xylose in prehydrolysate and glucose in enzymatic hydrolysate. The single factor experiment results showed that the conditions for maximum xylose recovery in prehydrolysate and glucose recovery in enzymatic hydrolysate were 60℃, 75 min, 10% solids and 160℃, 75 min, 10% solids, respectively. Whereafter, response surface methodology(RSM) was applied to further optimize the pretreatment conditions for the maximum theoretical ethanol production through utilizing both xylose and glucose. A treatment at 163℃, for 59 min and with 9.5%solids was found optimal, with the highest ethanol production of 20.2 mg·g^-1 raw material. Furthermore, in order to assess the impacts of the pretreatment on cassava anaerobic residue, the changes in crystallinity and morphology for untreated and pretreated solids were investigated.

关键词： Waste treatment Biofuel Hydrothermal Cassava anaerobic residue Co-utilization Response surface methodology

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以教育家精神为指引推进教材建设高质量发展

课程．教材．教法 2024年第2期44卷 4-6页

作者：田慧生首都师范大学北京100048

在第39个教师节到来之际,习近平总书记致信全国优秀教师代表,首次提出了教育家精神,勉励广大教师以教育家为榜样,大力弘扬教育家精神,为教育强国建设、民族复兴伟业作出新的更大贡献。我们要深入学习领会习近平总书记的重要指示要求,以... 详细信息

在第39个教师节到来之际,习近平总书记致信全国优秀教师代表,首次提出了教育家精神,勉励广大教师以教育家为榜样,大力弘扬教育家精神,为教育强国建设、民族复兴伟业作出新的更大贡献。我们要深入学习领会习近平总书记的重要指示要求,以教育家精神为指引,努力打造更多培根铸魂、启智增慧的精品教材,为培养德智体美劳全面发展的社会主义建设者和接班人贡献力量。

关键词：精品教材教育家精神教育强国启智教材建设民族复兴建设者和接班人德智体美劳

Multi-objective regulation in autohydrolysis process of corn stover by liquid hot water pretreatment

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Chinese Journal of Chemical Engineering 2017年第4期25卷 499-506页

作者： huisheng lü Xingfang Shi Yonghui li Fanmei Meng Shuangyan liu li Yan Key laboratory for Green Chemical Technology of Ministry of Education Tianjin University R&D Center for Petrochemical TechnologyTianjin UniversityTianjin 300072China

Increasing reducing sugars(xylose and glucose) yield for bioethanol from corn stover depends strongly on optimization of pretreatment conditions. The optimum reaction conditions of two-stage liquid hot water(lHW) pretreatment based on total sugars yield were investigated. Under optimal conditions, the recovery of glucose of corn stover after two-stage lHW pretreatment and 72 h enzymatic digestion, reached 89.55%. In addition, acetic acid-rich spent liquor pretreatment and one-stage lHW pretreatment have been carried out to make comparisons with two-stage lHW treatment. Glucose yield 89.55% is superior to the recovery 83.38% using acetic acidrich spent liquor pretreatment or 80.58% using one-stage lHW pretreatment. The production of total sugars was increased by 7.8% when compared with one-stage pretreatment. Moreover, the structural features of the treated corn stover solid residues were also investigated by XRD and SEM technology in order to clarify the effects of the reaction on corn stover. The results indicated that the two-stage lHW pretreatment was an effective pretreatment method of corn stover to get most massive resource utilization, and it could be successfully applied to corn stover.

关键词： Bioethanol 玉米 stover 液体热水预告的处理酶水解作用

Adsorption equilibria of paeoniflorin and albiflorin on cyano-silica column from supercritical carbon dioxide/ethanol

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Chinese Journal of Chemical Engineering 2019年第4期27卷 827-834页

作者： huisheng lü Zhi Wang Zhongfeng Geng Yonghui li Shuangyan liu Jiatao liu Key laboratory for Green Chemical Technology of Ministry of Education R&D Center for Petrochemical Technology Tianjin University Tianjin 300072 China Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300072 China

Adsorption equilibria of paeoniflorin and albiflorin on a cyano-silica column(CN column) from the solution of supercritical carbon dioxide(scCO2) modified with ethanol were studied. The adsorption capacity at 308.15 K,313.15 K, 318.15 K and 323.15 K under pressures corresponding to carbon dioxide/ethanol densities from0.347 g·cm^-3 to 0.662 g·cm^-3 were determined using the elution by characteristic point method(ECP). The effects of temperature and pressure on the solute loading were investigated. The results showed that the lower the temperature, the higher the adsorption capacity. With the decrease of density of scCO2, the adsorption capacity strengthens. The maximum adsorption capacity of paeoniflorin(albiflorin) on the CN column was15.24 mg·ml^-1(31.14 mg·ml^-1) in the range of 0–1.84 mg·ml^-1(0–1.67 mg·ml^-1) of paeoniflorin(albiflorin)standard solution. The adsorption capacity of albiflorin was twice as much as that of paeoniflorin under the same conditions. Adsorption data of paeoniflorin and albiflorin could be well described by the langmuir model and Freundlich model. Compared with the two model fitting results, the adsorption of paeoniflorin and albiflorin belonged to the monolayer adsorption under conditions of 308.15–323.15 K and 10–17 MPa.

关键词： Adsorption Supercritical carbon dioxide Paeoniflorin Albiflorin Isotherm model