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Collinear micro-shear-bands model for grain-size and precipitate-size effects on the yield strength

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Theoretical & Applied Mechanics Letters 2018年第4期8卷 245-251,298页

作者： yike Qiu Peng Zhang Lifeng ma S&V Lab Department of Engineering Mechanics Xi'an Jiaotong University Xi'an Thermal Power Research Institute Co. Ltd

Numerous experimental evidences show that the grain size may significantly alter the yield strength of metals.Similarly,innickel-based superalloys,the precipitate size also influences their yield strength.Then,how to describe such two kinds of size effects on the yield strength is a very practical challenge.In this study,according to experimental observations,a collinear micro-shear-bands model is proposed to explore these size effects on metal materials’yield strength.An analytical solution for the simple model is derived.It reveals that the yield strength is a function of average grain-size or precipitate-size,which is able to reasonably explain size effects on yield strength.The typical example validation shows that the new relationship is not only able to precisely describe the grain-size effect in some cases,but also able to theoretically address the unexplained Hall-Petch relationship between theprecipitate size and the yield strength of nickel-based superalloys.

关键词： Collinear micro-shear-bands model The Hall-Petch relationship γprecipitate Size effect

Review of harmless treatment of municipal solid waste incineration fly ash

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Waste Disposal and Sustainable Energy 2020年第1期2卷 1-25页

作者： yike Zhang Zengyi ma Zhuoting Fang Yuandong Qian Pucheng Zhong Jianhua Yan State Key Laboratory of Energy Clean Utilization Zhejiang UniversityHangzhou 310027China Ningbo Research Institute Zhejiang UniversityNingbo 315100China

Incineration is widely adopted in municipal solid waste management,which produces large amounts of municipal solid waste incineration(MSWI)fly ash.The harmless treatment of MSWI fly ash requires the appropriate disposal of heavy metals and dioxins that are enriched in fly ash.This review summarizes recently developed harmless disposal methods for MSWI fly ash including solidification/stabilization,thermal treatment,and separation/extraction.In addition,we discuss heavy metal and dioxin fixation,and the removal capacity of fly ash via solidification/stabilization(including cement solidification,chemical stabilization,hydrothermal processes,and mechano-chemical methods),thermal treatment(including sintering,fuel-burning,or electric melting/vitrification),and separation/extraction(including water-washing,chemical reagent leaching,biological leaching,electrodialysis separation,chemical reagent extraction,and nanomaterials extraction).The advantages and disadvantages of different harmless treatment methods are compared and future research prospects and suggestions are summarized.This review provides general guidelines for the harmless treatment of MSWI fly ash in the future.

关键词： Fly ash Municipal solid waste incineration Solidification/stabilization Thermal treatment Separation/extraction

Effects of seasonal changes on T-helper 1/T-helper 2 immune balance and eczema onset in rats

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Journal of Traditional Chinese Medical Sciences 2023年第1期10卷 64-72页

作者： Hairong Zhang Leilei Liu yike Sun Wenna Li Ruochong Wang Xiao Sun Guangqin Zhu Shuran ma School of Traditional Chinese Medicine Beijing University of Chinese MedicineBeijing 102488China Department of Acupuncture and Minimally Invasive Oncology Beijing University of Chinese Medicine Third Affiliated HospitalBeijing 100029China

Objective: To explore the impact of seasonal changes on the T-helper 1(Th1)/T-helper 2(Th2) immune balance of the body in order to elucidate the internal immunological mechanisms underlying seasonal eczema.Methods: Eighty 4-week-old male Sprague-Dawley rats were divided into 5 season groups kept in corresponding season simulation environments, and subdivided into the model group and the control group. The Eczema Area and Severity Index(EASI) and scratching frequency were evaluated. The serum levels of immunoglobulin E(IgE), interleukin-2(IL-2), interleukin-12(IL-12), and interferon-gamma(IFN-γ), interleukin-4(IL-4), interleukin-25(IL-25), and interleukin-31(IL-31), and melatonin(MT), as well as the MT receptor(MTR) levels in the spleen, were detected by enzyme-linked immunosorbent assay analysis. The mRNA expression levels of T-bet and GATA3 were detected by quantitative real-time polymerase chain reaction.Results: EASI scores and the scratching frequency of the model group were higher in the long summer than in the other 4 seasons. Meanwhile, the serum levels of IgE and the Th2 cytokines IL-4, IL-25, and IL-31, as well as GATA3 mRNA expression levels, were high during the long summer in both groups. However, the serum levels of the Th1 cytokines IL-2, IL-12, and IFN-γ, as well as MT, MTR, and T-bet mRNA levels, were lower during the long summer. In all 5 seasonal groups(spring, summer, long summer, autumn, and winter), the levels of all immune factors, especially IL-4 and IL-31, were higher in the model group than those in the control group,while the concentrations of MT and MTR were lower.Conclusion: Under long light, hot, and humid conditions in the long summer, the body is more likely to suffer from Th2-dominated immune imbalance. This is the internal mechanism behind the high incidence and severity of eczema during the long summer. MT and MTR play a key role in the seasonal onset of eczema.

关键词： Eczema Seasonality Long summer Immunization Th1/Th2 Melatonin Immunoglobulin E

Seasonal photoperiodic influence of pineal melatonin on hypothalamic-pituitary-adrenal axis-hippocampal-receptor in male rats

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Journal of Traditional Chinese Medical Sciences 2022年第2期9卷 143-152页

作者： Wenna Li Ting Li Leilei Liu Qi Han Hairong Zhang yike Sun Ruisen Hao Shuran ma School of Traditional Chinese Medicine Beijing University of Chinese MedicineBeijing102488China Community Health Service Center of Hailar East Road Office Hohhotthe Inner Mongolia Autonomous Region010015China School of Medicine Henan Polytechnic UniversityJiaozuo454000China

Background: Based on the effect of seasonal changes on human visceral function, this study investigated the impact of seasonal photoperiod of the pineal body on hypothalamic-pituitary-adrenal axis-hippocampal-receptor in rats, aiming to reveal the mechanism by which pineal gland melatonin regulates the seasonal secretion of hippocampal neurotransmitters.Methods: Vernal equinox, summer solstice, autumn equinox, and winter solstice were selected as four experimental time points, and rats were randomly divided into normal control group, sham operation group, and pinealectomized group. The seasonal changes in corticotropin-releasing hormone(CRH),adrenocorticotropic hormone(ACTH), corticosterone, hypothalamic melatonin receptor(MTR), and hippocampal corticosterone receptor(CORTR) were examined by enzyme-linked immunosorbent assay.Results: Comparing the same group between different seasons, we showed that in the normal control group, CRH, ACTH, corticosterone, and MTR were higher, while CORTR was lower in autumn and winter than in spring(all P mal control group, the pinealectomized group showed higher levels of corticosterone(P =.01), MTR(P =.01), and CORTR(P =.03) during spring;reduced levels of MTR and CORTR(both P may be the pathophysiological basis for the onset of seasonal affective disorder.

关键词： Pineal gland Melatonin Hippocampus Seasonal photoperiod Hypothalamic-pituitary-adrenal axis Receptor

Miocene Crustal Anatexis of Paleozoic Orthogneiss in the Zhada Area,Western Himalaya

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Acta Geologica Sinica(English Edition) 2022年第3期96卷 954-971页

作者： CHEN Han HU Guyue ZENG Lingsen YU Xuhui LI yike College of Earth Science Chengdu University of TechnologyChengdu 610059China MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China

Granitic gneiss(orthogneiss)and Himalayan leucogranite are widely distributed in the Himalayan orogen,but whether or not the granitic gneiss made a contribution to the Himalayan leucogranite remains unclear.In this study,we present the petrological,geochronological and geochemical results for orthogneisses and leucogranites from the Zhada area,Western Himalayas.Zhada orthogneiss is composed mainly of quartz,plagioclase,K-feldspar,biotite and muscovite,with accessory zircon and apatite.Orthogneiss zircon cathodoluminescence(CL)images show that most grains contain a core with oscillatory zoning,which indicates an igneous origin.Sensitive high-resolution ion microprobe(SHRIMP)U-Pb dating of the zircon cores in the orthogneiss shows a weighted ^(206)Pb/^(238)U age of 515±4 ma(early Paleozoic),with sponge-like zircon rims of 17.9±0.5 ma(Miocene).Zhada leucogranite shows^(206)Pb/^(238)U ages ranging from 19.0±0.4 ma to 12.4±0.2 ma,the weighted average age being 16.2±0.4 ma.The leucogranites have a low Ca content(malayan leucogranite derived from muscovite dehydration partial melting of metasediments and representative of most Himalayan leucogranites.The highly variable Na_(2)O+K_(2)O(4.33 wt%-9.13 wt%),Al_(2)O_(3)(8.44 wt%-13.51 wt%),ΣREE(40.2-191.0 ppm),Rb(67.0-402 ppm)and Nb(8.23-26.4 ppm)contents,^(87)Sr/^(86)Sr(t)ratios(0.7445-0.8605)andεNd(t)values(−3.6 to−8.2)indicate that the leucogranite is derived from a heterogenetic source.The nonradiogenic Nd isotope values of the studied Zhada leucogranite and orthogneiss range from−8.2 to−3.6 and from−8.7 to−4.1,respectively.Therefore,the general mixing equation was used to perform the Sr and Nd isotope mixing calculations.The results indicate that the heterogenetic source was the Tethyan Himalayan Sequence(THS)/Higher Himalayan Crystalline(HHC)metasediments and Zhada orthogneiss.The Zha

关键词： leucogranite orthogneiss petrogenesis crustal anatexis Zhada area Himalayan orogen

The Role of Mitochondria Fusion and Fission in Neuronal Death Induced by Cerebral Ischemia/Reperfusion

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The Role of Mitochondria Fusion and Fission in Neuronal Deat...

Epigenetic Modifications of mRNA and DNA in Plants

第十四届中国医师协会神经外科医师年会

作者： Chen yike Guo Songxue ma Feiqiang Luo Jinqi Wu Qun

Mitochondria are highly dynamic organelles which are joined by mitochondrial fusion and divided by mitochondrial fission. The balance of mitochondrial fusion and fission plays a critical role in maintaining the normal function of neurons. These processes are both mediated by several proteins, which could be affected by external stimulation. Cerebral ischemia-reperfusion（I/R） injury could destroy the homeostasis of the intracellular environment and disrupt the balance of mitochondrial fusion and fission through regulating the expression and post-translation modification of fusion and fission related proteins, thereby causing neuronal death. Furthermore human intervention in fusion and fission related proteins could influence the function of neurons and change the outcomes of cerebral I/R injury. In this review, we are aiming to highlight current development to help us understand the regulatory factors and signaling networks of aberrant mitochondrial fusion and fission contributing to neuronal death upon I/R, as well as the potential neuroprotective therapeutics targeting mitochondrial dynamics.

关键词： Ischemia/Reperfusion Mitochondria Fusion/Fission Neuronal Death

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Molecular Plant 2020年第1期13卷 14-30页

作者： Zhe Liang Adeel Riaz Sadaruddin Chachar yike Ding Hai Du Xiaofeng Gu biotechnology Research Institute Chinese Academy of Agricultural SciencesBeijing 100081China Centre for Organismal Studies Heidelberg UniversityHeidelberg 69120Germany Department of Entomology University of California RiversideRiversideCA 92521USA College of Agronomy and Biotechnology Southwest UniversityChongqing 400715China

Advances in the detection and mapping of messenger RNA(mRNA)N^6-methyladenosine(m 6A)and 5-methylcytosine(m 5C),and DNA N^6-methyldeoxyadenosine(6ma)redefined our understanding of these modifications as additional tiers of epigenetic regulation.In plants,the most prevalent internal mRNA modifications,m^6A and m^5C,play crucial and dynamic roles in many processes,including embryo development,stem cell fate determination,trichome branching,leaf morphogenesis,floral transition,stress responses,fruit ripening,and root development.The newly identified and widespread epigenetic marker 6ma DNA methylation is associated with gene expression,plant development,and stress responses.Here,we review the latest research progress on mRNA and DNA epigenetic modifications,including the detection,dynamics,distribution,functions,regulatory proteins,and evolution,with a focus on m^6A,m^5C,and 6ma.We also provide some perspectives on future research of the newly identified and unknown epigenetic modifications of mRNA and DNA in plants.

关键词： RNA modification m^6A m^5C DNA methylation 6ma epigenetics

Molecular mechanisms of seasonal photoperiod effects of the pineal gland on the hippocampus in rats

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Journal of Traditional Chinese Medical Sciences 2021年第2期8卷 135-144页

作者： Qi Han Guowen Du Leilei Liu Lepeng Wang Wenna Li Hairong Zhang yike Sun Pei Zhu Ruisen Hao Shuran ma School of Traditional Chinese Medicine Beijing University of Chinese MedicineBeijing102488China

Background:Based on the theory of“five Zang-organs corresponding to the seasons”in traditional Chinese medicine(TCM),physiological functions including emotions vary with the seasons.We aimed to investigate the seasonal photoperiod effects of melatonin(MT)released from the pineal gland on the MT receptor(MTR)-Gs/Gi-cyclic adenosine monophosphate(cAMP)-protein kinase A(PKA)-cAMP response element-binding protein(CREB)signaling pathway in the hippocampus.Methods:Rats were divided into three groups:control,operation(surgery with pineal gland removal),and pseudo-operation groups(same surgery as operation group but without removing pineal gland),and fed at specific time across the four seasons.The levels of MTR,adenylate cyclase(AC),cAMP,PKA,and CREB in the hippocampus were analyzed using ELISA.The concentrations of Gs and Gi were analyzed using Western blot.The expression of CREB mRNA was detected by PCR.Results:For intragroup comparisons,compared with spring,the levels of Gs/Gi in the control group were higher in summer,autumn,and winter(P=.009 in summer;Pmay underpin seasonal changes in emotions.It can support the prevention and treatment of the seasonal onset of mental disorders,and enrich the theory of“five Zang-organs corresponding to the seasons”.

关键词： Pineal gland Melatonin Hippocampus Photoperiod Signaling pathway

Dichlorination in a circulating fluidized-bed incinerator for municipal solid waste incineration system

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Waste Disposal and Sustainable Energy 2019年第3期1卷 207-212页

作者： Yaming Cai Zengyi ma Jianhua Yan yike Zhang Zhe Chen Ruofeng Gao Pucheng Zhong State Key Laboratory of Clean Energy Utilization/Ningbo Research Institute Zhejiang UniversityHangzhou 310027ZhejiangChina

Cl is one of the main pollutants emitted from domestic waste incineration systems. In this study, we focused on the process of Ca dechlorination in the furnace of a circulating fluidized-bed waste incineration system. We analyzed the stability of CaCl_(2) and Ca in the furnace, the dechlorination process, and distribution of Cl in the incineration system. The results show that the optimal Ca/Cl molar ratio for Ca dechlorination in the circulating fluidized-bed waste incinerator is 2:1;moreover, the dechlorination product CaCl_(2) was found to decompose at high temperatures (> 850℃). At temperatures > 700℃, we measured CaCl_(2) decomposition rates up to 80%. Ca was added in the furnace, mainly to provide a dechlorination Ca source for the decomposition of limestone into tail flue gas. The amount of Ca^(2+) in the flue decreased gradually, parallelly to the temperature of the flue gas. Stable CaCl_(2) was formed after HCl was captured, and relatively small solid particles appeared in the ash collecting bag.

关键词： Waste incineration HCl Ca-based Dichlorination