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In Situ/Operando(Soft) X-ray Spectroscopy Study of Beyond Lithium-ion Batteries

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Energy & Environmental Materials 2021年第2期4卷 139-157页

作者： Feipeng Yang Xuefei Feng Yi-Sheng Liu Li Cheng Kao per-Anders Glans Wanli Yang Jinghua Guo Joint Center for Energy Storage Research Lemont IL 60439USA Advanced Light Source Lawrence Berkeley National LaboratoryBerkeley CA 94720USA Department of Chemistry and Biochemistry University of California Santa CruzSanta Cruz CA 95064USA

The lightweight,rechargeable lithium-ion battery is one of the dominant energy storage devices globally in portable electronics due to its high energy density,no memory effect,wide operating voltage,lightweight,and good charge ***,due to safety concerns,the depletion of lithium reserves,and the corresponding increase of cost,an alternative battery system becomes more and more *** develop alternative battery systems with low cost and high material abundance,for example,sodium,magnesium,zinc,and calcium,it is important to understand the chemical and electronic structure of *** X-ray spectroscopy,for example,X-ray absorption spectroscopy(XAS),X-ray emission spectroscopy(XES),and resonant inelastic soft X-ray scattering(RIXS),is an element-specific technique with sensitivity to the local chemical environment and structural order of the element of *** soft X-ray systems enable operando experiments that can be applied to amorphous and crystalline samples,making it a powerful tool for studying the electronic and structural changes in electrode and electrolyte *** this article,the application of in situ/operando(soft)X-ray spectroscopy in beyond lithium-ion batteries is reviewed to demonstrate how such spectroscopic characterizations could facilitate the interpretation of interfacial phenomena under in situ/operando condition and subsequent development of the beyond lithium-ion batteries.

关键词： (soft)X-ray spectroscopy beyond lithium-ion battery in situ/operando interface

New insights into substrate folding preference of plant OSCs

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Science Bulletin 2016年第18期61卷 1407-1412页

作者： Yongshuo Ma Yuan Zhou Sergey Ovchinnikov per Jr.Greisen Sanwen Huang Yi Shang Institute of Vegetables and Flowers Chinese Academy of Agricultural Sciences Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture Sino-Dutch Joint Laboratory of Horticultural Genomics Department of Biochemistry University of Washington Department of Modelling Novo Nordisk A/S 2760 Ml?vDenmark Agricultural Genomic Institute at Shenzhen Chinese Academy of Agricultural Sciences

Sterols and triterpenes are structurally diverse bioactive molecules generated through cyclization of linear 2,3-oxidosqualene. Based on carbocationic intermediates generated during initial substrate preorganization step, oxidosqualene cyclases （OSCs） are roughly segregated into protosteryl cation group that mainly catalyzes tetracyclic products and dammarenyl cation group which mostly generates pentacyclic products. However, in contrast to well-studied cascade of ring-forming reactions, little is known about the mechanism underlying the initial sub- strate folding process. Previously, we have identified a cucurbitadienol synthase （Bi） and its null allele bi （C393Y） from cucumber. By integration of homology modeling, residue coevolution and site-directed mutagenesis, we discover that four covarying amino acids including C393 constitute a dynamic domain that may be involved in substrate folding process for Bi. We also reveal a group of co-conserved residues that closely associated with the segregation of plant OSCs. These residues may act col- laboratively in choice of specific substrate folding inter- mediate for OSCs. Thus, engineer plant OSCs from into five-ringed producer. our findings open a door to four-ringed skeleton catalysts

关键词： Oxidosqualene cyclase Homologymodeling Residue coevolution Substrate folding

Atomistic learning in the electronically grand-canonical ensemble

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npj Computational Materials 2023年第1期9卷 1619-1627页

作者： Xi Chen Muammar El Khatib per Lindgren Adam Willard Andrew J.Medford Andrew A.Peterson School of Engineering Brown UniversityProvidenceRI 02912USA Department of Chemistry Massachussetts Institute of TechnologyCambridgeMAUSA School of Chemical and Biomolecular Engineering Georgia Institute of TechnologyAtlantaGA 30318USA

A strategy is presented for the machine-learning emulation of electronic structure calculations carried out in the electronically grand-canonical *** approach relies upon a dual-learning scheme,where both the system charge and the system energy are predicted for each *** scheme is shown to be capable of emulating basic electrochemical reactions at a range of potentials,and coupling it with a bootstrap-ensemble approach gives reasonable estimates of the prediction *** method is also demonstrated to accelerate saddle-point searches,and to extrapolate to systems with one to five water *** anticipate that this method will allow for larger length-and time-scale simulations necessary for electrochemical simulations.

关键词： canonical ensemble electronic

Nitrite,a novel method to decrease ischemia/reperfusion injury in the rat liver

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World Journal of Gastroenterology 2015年第6期21卷 1775-1783页

作者： Bergthor Bjrnsson Linda Bojmar Hans Olsson Tommy Sundqvist per Sandstrm Department of Surgery County Council of ?sterg?tland Department of Clinical and Experimental Medicine Faculty of Health Sciences Link?ping University Department of Pathology County Council of ?sterg?tland

AIM:To investigate whether nitrite administered prior to ischemia/reperfusion(I/R)reduces liver ***:Thirty-six male Sprague-Dawley rats were randomized to 3 groups,including sham operated(n=8),45-min segmental ischemia of the left liver lobe(IR,n=14)and ischemia/reperfusion(I/R)preceded by the administration of 480 nmol of nitrite(n=14).Serum transaminases were measured after 4 h of *** microdialysate(MD)was sampled in 30-min intervals and analyzed for glucose,lactate,pyruvate and glycerol as well as the total nitrite and nitrate(NOx).The NOx was measured in ***:Aspartate aminotransferase(AST)at the end of reperfusion was higher in the IR group than in the nitrite group(40±6.8μkat/L vs 22±2.6μkat/L,P=0.022).Similarly,alanine aminotransferase(ALT)was also higher in the I/R group than in the nitrite group(34±6μkat vs 14±1.5μkat,P=0.0045).The NOx in MD was significantly higher in the nitrite group than in the I/R group(10.1±2.9μmol/L vs 3.2±0.9μmol/L,P=0.031)after the administration of *** ischemia,the levels decreased in both groups and then increased again during *** the end of reperfusion,there was a tendency towards a higher NOx in the I/R group than in the nitrite group(11.6±0.7μmol/L vs 9.2±1.1μmol/L,P=0.067).Lactate in MD was significantly higher in the IR group than in the nitrite group(3.37±0.18 mmol/L vs 2.8±0.12 mmol/L,P=0.01)during ischemia and the first 30 min of *** the same period,glycerol was also higher in the IRI group than in the nitrite group(464±38μmol/L vs 367±31μmol/L,P=0.049).With respect to histology,there were more signs of tissue damage in the I/R group than in the nitrite group,and29%of the animals in the I/R group exhibited necrosis compared with none in the nitrite *** nitric oxide synthase transcription increased between early ischemia(t=15)and the end of reperfusion in both ***:Nitrite administered before liver ischemia in the rat liver redu

关键词： Ischemia-reperfusion injury Nitrite Liver ischemia

Laparoscopic surgery for benign and malign diseases of the digestive system:Indications,limitations,and evidence

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World Journal of Gastroenterology 2014年第17期20卷 4883-4891页

作者： Markus Alexander Küper Friederike Eisner Alfred K?nigsrainer J?rg Glatzle Department for General and Visceral Surgery Bundeswehr Hospital BerlinD-10115 BerlinGermany Department for General Visceral and Transplant SurgeryUniversity Hospital Tübingen72076 TübingenGermany

The laparoscopic technique was introduced in gastrointestinal surgery in the mid 1980s. Since then, the development of this technique has been extraordinary. Triggered by technical innovations (stapling devices or coagulation/dissecting devices), nowadays any type of gastrointestinal resection has been successfully performed laparoscopically and can be performed laparoscopically dependent on the patient’s condition. This summary gives an overview over 30 years of laparoscopic surgery with focus on today’s indications and evidence. Main indications remain the more common procedures, e.g., appendectomy, cholecystectomy, bariatric procedures or colorectal resections. For all these indications, the laparoscopic approach has become the gold standard with less perioperative morbidity. Regarding oncological outcome there have been several high-quality randomized controlled trials which demonstrated equivalency between laparoscopic and open colorectal resections. Less common procedures like esophagectomy, oncological gastrectomy, liver and pancreatic resections can be performed successfully as well by an experienced surgeon. However, the evidence for these special indications is poor and a general recommendation cannot be given. In conclusion, laparoscopic surgery has revolutionized the field of gastrointestinal surgery by reducing perioperative morbidity without disregarding surgical principles especially in oncological surgery.

关键词： Laparoscopy Gastrointestinal surgery Esophagus Stomach Cholecystectomy Colorectal surgery Liver resection Pancreas resection Laparoscopic resection of gastrointestinal

Fluorescence of Single Conjugated Chains of MEH-PPV Dispersed in Polymer Matrix: What Do We See in the Microscope?

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Chinese Journal of Chemistry 2023年第19期41卷 2536-2544页

作者： Mingyi Xie Marina V.Kuzimenkova per-Olof Larsson Yuxi Tian Ivan G.Scheblykin Key Laboratory of Mesoscopic Chemistry of MOE School of Chemistry and Chemical EngineeringNanjing UniversityNanjingJiangsu210023 China Chemical Physics and NanoLund Lund UniversityPO Box 124SE-22100 LundSweden Pure and Applied Biochemistry Lund UniversityPO Box 124SE-22100 LundSweden

It has been a mystery that the detected fluorescence intensity of single MEH-PPV molecules is much lower than expected based on their chain *** this review,after re-evaluating of the literature data in the light of new specially designed experiments,we present a comprehensive explanation of this issue:The actual size of MEH-PPV molecules at single molecule level is much smaller than expected due to de-aggregation and chain scission,while static quenching("dark matter")also exists for large molecules,further reducing their brightness.

关键词： MEH-PPV Single molecule spectroscopy Brightness Fluorescence Molecular weight anrohonci

Pre-sowing treatment for breaking dormancy in Acer velutinum Boiss. seed lots

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Journal of Forestry Research 2013年第2期24卷 273-278页

作者： Mostafa Farhadi Mulualem Tigabu Alireza Ghasemi Arian Mehdi Sharifani Abolfazl Daneshvar per Christer Oden Swedish University of Agricultural Sciences Southern Swedish Forest Research Centre Education Center of Jihad-Agriculture Gorgan University of Agricultural Sciences and Natural Resources Horticulture Department

Acer velutinum Boiss is a valuable tree species native to Iran, and its seeds possess physiological dormancy that hampers seedling production in the nursery for large-scale reforestation efforts. The aim of this study was to determine the optimal dormancy breaking treatments for A. velutinum seeds. We conducted a factorial experiment involving six seed lots collected along an elevation gradient from 300 to 1800 m at 300 m interval and four cold-moist stratification periods （0, 4, 8 and 16 weeks） at 4℃ and 70% relative humidity. The result shows that the germination of cold-moist stratified seeds was significantly （p 〈 0.0001） higher than the control for all seed lots. The highest germination capacity was recorded after 16 weeks of cold-moist stratification for all seed lots （68% 88% depending on the seed lot） except those collected from mid altitude sites （600 and 900 m） that germinated equally well （≥ 75%） after 4and 8-week of clod-moist stratification compared to the other seed lots. The mean germination time was significantly shorter （12 to 19 days, depending on the seed lot） for seeds stratified for 16 weeks than for untreated seeds. It can be concluded that：（1） cold-moist stratification for 16 weeks is the best pre-sowing treatment for breaking dormancy in A. velutinum seeds; and （2） seeds should be collected from mid altitude sites （600 and 900 m） to get more than 80% germination within 15 days, and these seed lots even required shorter cold-moist stratification period（eight weeks） than other seed lots.

关键词： cold-stratification altitude physiological dormancy velvet maple seed germination

Document Type Profiles in Nature, Science, and PNAS： Journal and Country Level

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Journal of Data and Information Science 2016年第3期1卷 27-41页

作者： Jielan Ding per Ahlgren Liying Yang Ting Yue National Science Library Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China School of Education and Communication in Engineering Sciences (ECE) KTH Royal Institute of Technology Stockholm 10044 Sweden

Purpose： In this contribution, we want to detect the document type profiles of the three prestigious journals Nature, Science, and Proceedings of the National Academy of Sciences of the United States （PNAS） with regard to two levels： journal and country. Design/methodology/approach： Using relative values based on fractional counting, we investigate the distribution of publications across document types at both the journal and country level, and we use （cosine） document type profile similarity values to compare pairs of publication years within countries. Findings： Nature and Science mainly publish Editorial Material, Article, News Item and Letter, whereas the publications of PNAS are heavily concentrated on Article. The shares of Article for Nature and Science are decreasing slightly from 1999 to 2014, while the corresponding shares of Editorial Material are increasing. Most studied countries focus on Article and Letter in Nature, but on Letter in Science and PNAS. The document type profiles of some of the studied countries change to a relatively large extent over publication years. Research limitations： The main limitation of this research concerns the Web of Science classification of publications into document types. Since the analysis of the paper is based on document types of Web of Science, the classification in question is not free from errors, and the accuracy of the analysis might be *** implications： Results show that Nature and Science are quite diversified with regard to document types. In bibliometric assessments, where publications in Nature and Science play a role, other document types than Article and Review might therefore be taken into account. Originality/value： Results highlight the importance of other document types than Article and Review in Nature and Science. Large differences are also found when comparing the country document type profiles of the three journals with the corresponding profiles in all Web of Science journals.

关键词： Country Document type profile Nature Science Proceedings of the NationalAcademy of Sciences of the United States of America (PNAS)

Response of soil fauna to simulated nitrogen deposition: A nursery experiment in subtropical China

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Journal of Environmental Sciences 2007年第5期19卷 603-609页

作者： XU Guo-liang MO Jiang-ming FU Sheng-lei per Gundersen ZHOU Guo-yi XUE Jing-Hua Institute of Ecology South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China Danish Center for Forest Landscape and Planning KVL Hoersholm Kongevej 11 DK-2970 Hoersholm Denmark

We studied the responses of soil fauna to a simulated nitrogen deposition in nursery experimental plots in Subtropical China. Dissolved NH4NO3 was applied to the soil by spraying twice per month for 16 months, starting January 2003 with treatments of 0, 5, 10, 15 and 30 gN/（m^2·a）. Soil fauna was sampled after 6, 9, 13 and 16 months of treatment in three soil depths （0-5 cm, 5-10 cm, 10-15 cm）. Soil available N increased in correspondence with the increasing N treatment, whereas soil pH decreased. Bacterial and fungal densities were elevated by the N treatment. Soil fauna increased in the lower nitrogen treatments but decreased in the higher N treatments, which might indicate that there was a threshold around 10 gN/（m^2·a） for the stimulating effects of N addition. The N effects were dependent on the soil depth and sampling time. The data also suggested that the effects of the different N treatments were related to the level of N saturation, especially the concentration of NO3^- in the soil.

关键词： soil fauna N deposition response Subtropical China