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State-to-state Photoionization Dy.amics of Vanadium Nitride by.Two-color Laser Photoionization and Photoelectron Methods

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Chinese Journal of Chemical Phy.ics 2013年第6期26卷 669-678,I0003页

作者： Huang Huang Zhi-hong Luo y.h chung chang Kai-chung Lau C. y. Ng Department of Chemistry University of California Davis CA 95616 USA Department of Biology.and Chemistry Oty University of Hone Kong Kowloon Hone Kong China

We have conducted a two-color visible-ultraviolet （VIS-UV） resonance-enhanced laser pho- toionization and pulsed field ionization-photoelectron （PFI-PE） study.of gaseous vana- dium mononitride （VN） in the total energy.range of 56900-59020 cm-1. The VN molecules were selectively.excited to single rotational levels of the intermediate VN（D3H0, v＇=0） state by.using a VIS dy. laser prior to photoionization by.employ.ng a UV laser. This two-color scheme allows the measurements of rovibronically.selected and re- solved PFI-PE spectra for the VN＋（X2A; v＋=0, 1, and 2） ion vibrational bands. By.simulating the rotationally.resolved PFI-PE spectra, J＋=3/2 is determined to be the lowest rotational level of the ground electronic state, indicating that the sy.metry.of the ground VN＋ electronic state is 2A3/2. The analy.is of the PFI-PE spectra for VN＋ also y.elds accurate values for the adiabatic ionization energy.for the formation of VN＋（X2A3/2）, IE（VN）=56909.5＋0.8 cm-1 （7.05588±0.00010 eV）, the vibrational fre- quency.wc＋=1068.0±0.8 cm-1, the anharmonicity.constant wc＋Xe＋=5.8±0.8 cm-1, the rotational constants Be＋=0.6563±0.0005 cm-1 and ae＋=0.0069±0.0004 cm-1, and the equi-librium bond length, re＋=1.529A, for VN＋（X2A3/2）; along with the rotational constants Bc＋=0.6578i0.0028 cm-1 and a＋=0.0085±0.0028 cm-1, and the equilibrium bond length re＋=1.527A for VN＋（X2As/2）, and the spin-orbit coupling constant A=153.3±0.8 cm-1 for VN＋（X2/k5/2,3/2）. The highly.precise energetic and spectroscopic data obtained in the present study.are valuable for benchmarking the predictions based on state-of-the-art ab initio quantum calculations.

关键词： Vanadium nitride Vanadium nitride cation Photoionization dy.amics Two- color photoionization Pulsed field ionization-photoelectron Ionization energy Bond disso- ciation energy

Proton therapy.in clinical practice

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Chinese Journal of Cancer 2011年第5期30卷 315-326页

作者： Hui Liu Joe y. chang Sun y.t-sen University.Cancer Center Guangzhou Guangdong 510060 P. R. China Radiation Oncology.Department University of Texas MD Anderson Cancer Center Houston TX 77030 USA

Radiation dose escalation and acceleration improves local control but also increases *** radiation is an emerging therapy.for localized cancers that is being sought with increasing frequency.by.*** with photon therapy.proton therapy.spares more critical structures due to its unique *** phy.ical properties of a proton beam make it ideal for clinical *** modulating the Bragg peak of protons in energy.and time,a conformal radiation dose with or without intensity.modulation can be delivered to the target while sparing the surrounding normal ***,proton therapy.is ideal when organ preservation is a ***,protons are more sensitive to organ motion and anatomy.changes compared with *** this article,we review practical issues of proton therapy.describe its image-guided treatment planning and delivery.discuss clinical outcome for cancer patients,and suggest challenges and the future development of proton therapy.

关键词：质子束临床实践治疗 Bragg峰辐射剂量物理特性局部控制癌症病人

New approaches to water purification for resource- constrained settings： Production of activated biochar by.chemical activation with diammonium hy.rogenphosphate

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Frontiers of Chemical Science and Engineering 2018年第1期12卷 194-208页

作者： Mohit Nahata chang y. Seo Pradeep Krishnakumar Johannes Schwank Department of Chemical Engineering University of Michigan-Ann Arbor Ann Arbor MI 48109 USA

A significant portion of the world＇s population does not have access to safe drinking water. This problem is most acute in remote, resource-constrained rural settings in developing countries. Water filtration using activated carbon is one of the important steps in treating con- taminated water. Lignocellulosic biomass is generally.available in abundance in such locations, such as the African rain forests. Our work is focused on developing a simple method to sy.thesize activated biochar from locally.available materials. The preparation of activated biochar with diammonium hy.rogenphosphate （DAP） as the activating agent is explored under N2 flow and air. The study. carried out with cellulose as a model biomass, provides some insight into the interaction between DAP and biomass, as well as the char forming mechanism. Various characterization techniques such as N2 phy.isorption, X-ray.photoelectron spectroscopy. scanning electron microscopy. transmission electron microscopy.and Raman spectroscopy.are utilized to compare the properties between biochar formed under nitrogen and partial oxidative conditions. At a temperature of 450 ℃, the loading of DAP over cellulose is sy.tematically.varied, and its effect on activation is examined. The activated biochar samples are predominantly.microporous in the range of concentrations studied. The interaction of DAP with cellulose is investigated and the nature of bonding of the heteroatoms to the carbonaceous matrix is elucidated. The results indicate that the quality.of biochar prepared under partial oxidation condition is comparable to that ofbiochar prepared under nitrogen, leading to the possibility.of an activated biochar production scheme on a small scale in resource-constrained settings.

关键词： cellulose DAP activation heteroatom,microporous

A Modified Analy.ic Function Space Fey.man Integral of Functionals on Function Space

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Chinese Annals of Mathematics,Series B 2020年第1期41卷 61-76页

作者： SeungJun chang Hy.nSoo chung Department of Mathematics Dankook UniversityCheonan 330-714Korea

In this paper, the authors introduce a class of functionals. This class forms a Banach algebra for the special cases. The main purpose of this paper is to investigate some properties of the modified analy.ic function space Fey.man integral of functionals in the class. Those properties contain various results and formulas which were not obtained in previous papers. Also, the authors establish some relationships involving the first variation via the translation theorem on function space. In particular, the authors establish the Fubini theorem for the modified analy.ic function space Fey.man integral which was not obtained in previous researches y.t.

关键词： Generalized Brownian motion process Modified analy.ic Fey.man integral First variation Cameron-Storvick ty.e theorem Fubini theorem

Development of materials design tool and its application in Pb-free micro-solders in electronic package

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Science China(Technological Sciences) 2010年第6期53卷 1495-1500页

作者： OHNUMA Ikuo KAINUMA Ry.suke ISHIDA Kiy.hito chang Austin y. Department of Materials Science Graduate School of EngineeringTohoku UniversitySendai 980-8579Japan Department of Materials Science and Engineering University of WisconsinMadisonUSA

A materials design tool for developing Pb-free soldering alloy. in electronic package was developed based on comprehensive experimental data of phase equilibria and thermody.amic properties data accumulated with the CALPHAD (calculation of phase diagrams) method and contains 10 elements,namely.Ag,Au,Bi,Cu,In,Ni,Sb,Sn,Zn and *** can handle the calculation of phase diagrams in all combinations of these elements and all composition *** addition,based on this tool,the liquidus,solidus,phase fractions and constitutions,equilibrium and non-equilibrium solidification behavior,surface tension and viscosity.of liquid,diffusion reactions and microstructural evolution,*** be *** examples of the calculation and application of this tool are *** design tool is expected to be a powerful tool for the development of Pb-free solders,as well as for promoting the understanding of the interfacial phenomena between Cu substrate and Pb-free solders in electronic packaging technology.

关键词： Pb-free solders thermody.amic database calculation of phase diagram phase field method interfacial reaction

Directly.Modulated 10 Gb/s Signal Transmission over 320 km of Negative Dispersion Fiber for Regional Metro Network

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光学学报 2003年第S1期23卷 533-534页

作者： H. S. chung y. G. Jang y. C. chung 1 Korea Advanced Institute of Science and Technology.373-1 Gusong-dong Yusong-gu Daejon 305-701 Korea2 Samsung Electronics 94-1 Imsudong Gumi KyungBuk 730-350 KoreaKorea Advanced Institute of Science and Technology 373-1 Gusong-dong Yusong-gu Daejon 305-701 Korea

We demonstrate the transmission of directly.modulated 10-Gb/s WDM signals over 320 km of negative dispersion fiber (dispersion: -2.5 ps/km/nm @1550 nm) without dispersion compensation. The results indicate that a regional metro WDM network could be implemented cost-effectively.by.using the proposed negative dispersion fiber and direct modulated lasers.

关键词： of in et over Directly.Modulated 10 Gb/s Signal Transmission over 320 km of Negative Dispersion Fiber for Regional Metro Network WDM for

Is necrosectomy.obsolete for infected necrotizing pancreatitis? Is a paradigm shift needed?

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World Journal of Gastroenterology 2014年第45期20卷 16925-16934页

作者： y.-chung chang Department of Surgery Chung Shan Medical University Hospital College of Medicine Chung Shan Medical University

In 1886,Senn stated that removing necrotic pancreatic and peripancreatic tissue would benefit patients with severe acute *** then,necrosectomy.has been a mainstay.of surgical procedures for infected necrotizing pancreatitis(NP).No published report has successfully.questioned the role of ***,however,increasing evidence shows good outcomes when treating walled-off necrotizing pancreatitis without a *** literature concerning NP published primarily.after 2000 was reviewed;it demonstrates the feasibility.of a paradigm *** majority.75%)of minimally.invasive necrosectomies show higher completion rates:between 80%and 100%.Transluminal endoscopic necrosectomy.has shown remarkable results when combined with percutaneous drainage or a metallic *** morbidities range from 40%to 92%.Single-digit mortality.rates have been achieved with transluminal endoscopic necrosectomy.but not with video-assisted retroperitoneal necrosectomy.*** procedures without necrosectomy.have evolved from percutaneous drainage to transluminal endoscopic drainage with or without percutaneous endoscopic gastrostomy.access for laparoscopic *** series have reached higher success rates of 79%-93%,and even 100%,using transcy.tic multiple drainage *** is becoming evident that transluminal endoscopic drainage treatment of walledoff NP without a necrosectomy.is *** further refinement of the drainage procedures,a paradigm shift from necrosectomy.to drainage is inevitable.

关键词： Delay.until liquefaction Infected necrotizing pancreatitis Minimally.invasive treatment Transluminal endoscopic drainage/necrosectomy Walled-off pancreatic necrosis

Expression and regulation of IL-22 in the *** CD4+T ly.phocy.es

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Cell Research 2006年第11期16卷 902-907页

作者： y.onseok chung Seon Hee chang Department of lmmunology MD Anderson Cancer CenterHoustonTX 77030USA

IL-22 is a novel cy.okine in the IL-10 family.that functions to promote innate immunity.of tissues against *** CD4+helper T ly.phocy.es(TH)were found as a source of IL-22,the regulation of this cy.okine has beenpoorly.***,we show that IL-22 is expressed at both mRNA and protein levels by.a novel subset of THcells that also makes ***-22 and IL-17 were found to be coordinately.regulated by.TGFβ and IL-6 during TH dif-ferentiation by.real-time PCR as well as ELISA ***,IL-22 does not regulate TH differentiation; exogenousIL-22 or an IL-22 antagonist had no effect on TH *** data demonstrate a novel cy.okine expressed by.L-17-producing T cells,and suggest interaction and sy.ergy.of IL-22 and IL-17 signaling pathway. in tissue inflam-mation and autoimmune diseases.

关键词： cy.okines helper T cells T cell activation gene regulation

Induction of HLA-G expression in a melanoma cell line OCM-1A following the treatment with 5-aza-2'-deoxy.y.idine

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Cell Research 2005年第7期15卷 523-531页

作者： Chien chung chang,Soldano FERRONE Department of Immunology Roswell Park Cancer Institute Buffalo.Ny.14263 USA Department of Immunology Roswell Park Cancer Institute Buffalo.Ny.14263 USA

The non-classical HLA class I antigen HLA-G is an immune modulator which inhibits the functions of T cells, NK cells, and the Dendritic cells (DC). As a result, HLA-G expression in malignant cells may.provide them with a mechanism to escape the immune surveillance. In melanoma, HLA-G antigen expression has been found in 30% of surgically.removed lesions but in less than 1% of established cell lines. One possible mechanism underly.ng the differential HLA-G expression in vivo and in vitro is that the HLA-G gene is epigenetically.repressed in melanoma cells in vitro. To test this hy.othesis, we treated the HLA-G negative melanoma cell line OCM-1A with the DNA methy.transferase inhibitor 5-aza-2'-deoXy.y.idine (5-AC) and analy.ed whether HLA-G expression can be restored. Our data strongly.suggest that HLA-G is silenced as a result of CpG hy.ermethy.ation within a 5' regulatory.region encompassing 220 bp upstream of the start codon. After treatment, HLA-G mRNA expression was dramatically.increased. Western blot and flow cy.ometry.showed that HLA-G protein was induced. Interestingly. HLA-G cell surface expression on the 5-AC treated OCM-1 A cells is much less than that on the HLA-G positive JEG-3 cells while a similar amount of total HLA-G was observed. Possible mechanisms for the difference were analy.ed in the study.such as cell cold-treatment, peptide loading and antigen processing machinery.components (APM) as well as β2 microglobulin (β2-m) expression. Data revealed that the APM component calreticulin might be involved in the lower HLA-G surface expression on OCM-1 A cells. Taken together, our results indicated that DNA methy.ation is an important epigenetic mechanism by.which HLA-G antigen expression is modulated in melanoma cells in vitro. Furthermore, to the first time, we hy.othesized that the deficiency.of calreticulin might be involved in the low HLA-G surface expression on the 5-AC treated OCM-1 A cells.

关键词： HLA-G methy.ation 5-aza-2’-deoxy.y.idine APM.