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NitroMAC：An instrument for the measurement of HONO and intercomparison with a long-path absorption photometer

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Journal of Environmental Sciences 2016年第2期28卷 105-113页

作者： Charbel Afif Corinne Jambert vincent Michoud Aurélie Colomb gregory Eyglunent Agnès Borbon véronique Daele Jean-Francois Doussin Pascal Perros Emissions Measurements and Modeling of the Atmosphere Laboratory EGFEM Unit Center for Analysis and Research Faculty of SciencesSaint Joseph University Beirut Lebanon Laboratoire Interuniversitaire des Systemes Atmospheriques (LISA) UMR7583 CNRS Universite Paris-Est-Creteil (UPEC) et Universite Paris Diderot (UPD) Institut Pierre Simon Laplace (IPSL) Creteil France Institut de Combustion Aerothermique Reactivite et Environnement CNRS Orleans France

Nitro MAC（French acronym for continuous atmospheric measurements of nitrogenous compounds） is an instrument which has been developed for the semi-continuous measurement of atmospheric nitrous acid（HONO）. This instrument relies on wet chemical sampling and detection using high performance liquid chromatography（HPLC）-visible absorption at540 nm. Sampling proceeds by dissolution of gaseous HONO in a phosphate buffer solution followed by derivatization with sulfanilamide/N-（1-naphthyl）-ethylenediamine. The performance of this instrument was found to be as follows： a detection limit of around 3 ppt with measurement uncertainty of 10% over an analysis time of 10 min. Intercomparison was made between the instrument and a long-path absorption photometer（LOPAP） during two experiments in different environments. First, air was sampled in a smog chamber with concentrations up to 18 ppb of nitrous acid. Nitro MAC and LOPAP measurements showed very good agreement. Then, in a second experiment, ambient air with HONO concentrations below250 ppt was sampled. While Nitro MAC showed its capability of measuring HONO in moderate and highly polluted environments, the intercomparison results in ambient air highlighted that corrections must be made for minor interferences when low concentrations are measured.

关键词： Atmospheric measurements Nitrous acid Sulfanilamide/N-(1-naphthyl)-ethylenediamine Long-path absorption photometer French acronym for continuous atmospheric measurements of nitrogenous compounds(NitroMAC)

Forest observational studies-an essential infrastructure for sustainable use of natural resources

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Forestry Studies in China 2014年第2期16卷 61-70页

作者： XiuHai Zhao Javier Corral-Rivas ChunYu Zhang Hailemariam Temesgen Klaus v gadow Beijing Forestry University Universidad Autonóma de Nuevo León DurangoMéxico Oregon State University CorvallisUSA Burckhardt Institute Georg-August UniversityGttingenGermany Institute of Forestry and Wood Science University of StellenboschStellenboschSouth Africa

This contribution complements Forest Ecosystems＇ Thematic Series on ＂Forest Observational Studies＂. We provide essential clarification regarding the definition and purpose of long-term field studies, review some of the extensive literature and discuss different approaches to collecting field data. We also describe two newly established forest observational networks that serve to illustrate the scope and diversity of forest field studies. The first is a large-scale network of forest observational studies in prominent natural forest ecosystems in China. The second example demonstrates observational studies in mixed and uneven-aged pine-oak forests which are selectively managed by local communities in Mexico. We summarize the potential for analysing and modeling forest ecosystems within interdisciplinary projects and provide argumentation in favour of long-term institutional commitment to maintaining forest observational field studies.

关键词： Mexico China India Longitudinal Cross-sectional Interval study Experiment Social media surveillance

Nanostructures formation in ferroelectrics in the process of phase transformation

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Journal of Advanced Dielectrics 2014年第4期4卷 32-41页

作者： v.Ishchuk N.Spiridonov v.Sobolev Science and Engineering Center\Reaktivelektron"of the National Academy of Sciences of Ukraine 83096 Donetsk Ukraine Department of Physics South Dakota School of Mines and Technology Rapid City SD 57701USA

Received 26 June 2014;Revised 13 October 2014;Accepted 20 October 2014;Published 12 November 2014 Inhomogeneous states caused by the coexistence of the ferroelectric(FE)and antiferroelectric(AFE)phases in lead–zirconate–titanate based solid solutions have been *** has been found that the domains of the FE and AFE phases with sizes of the order of 20 nm to 30 nm coexist in the bulk of the samples due to a small difference in the free energies of these *** coherent character of the interphase boundaries(IPBs)leads to the concentration of the elastic stresses along these *** elastic stresses cause the local decomposition of the solid solution and formation of segregates near the IPBS due to the condition that equivalent positions of the crystal lattice are occupied by the ions with different *** sizes of the segregates formed in this way are of the order 8 nm to 15 *** physical effects caused by the presence of these segregate nanostructures are analyzed and discussed.

关键词： Ferroelectrics antiferroelectrics phase transitions phase coexistence interdomain boundaries local decomposition of solid solutions

Experimental Investigation of Transmission Properties and All-Optical Label Swapping of Orthogonal IM/FSK Labeled Signals

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光学学报 2003年第S1期23卷 679-680页

作者： Pablo v. Holm-Nielsen Christophe Peucheret Idelfonso Tafur Monroy Palle Jeppesen Research Center COM Technical University of Denmark 2800 Kgs. Lyngby DenmarkResearch Center COM Technical University of Denmark 2800 Kgs. Lyngby DenmarkCOBRA Research Institute Eindhoven University of Technology The NetherlandsResearch Center COM Technical University of Denmark 2800 Kgs. Lyngby Denmark

OpticallylabeledIM/FSKsign***-optical label swapping based on MZ-SOA and EAM is presented. Transmission followed by label swapping shows a 2dB overall power penalty.

关键词： FSK on of IM Experimental Investigation of Transmission Properties and All-Optical Label Swapping of Orthogonal IM/FSK Labeled Signals EAM SOA that into

用2-羟苯乙酮肟萃取和同时分光光度测定混合物中钒(Ⅳ)和钒(Ⅴ)

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湿法冶金 1990年第2期9卷 80-83页

作者： g.v.Ramana Murthy 游建南

在pH范围分别为3.6—4.5和2.7—4.1的条件下,在2-羟苯乙酮肟存在时,钒(Ⅳ)和钒(Ⅴ)可定量地萃入氯仿中。对有机层进行测定,钒(Ⅳ)和钒(Ⅴ)分别在345和350nm处显示出最大的吸收。对钒(Ⅳ)在350nm波长处的行为也进行了研究。在380nm以外,... 详细信息

在pH范围分别为3.6—4.5和2.7—4.1的条件下,在2-羟苯乙酮肟存在时,钒(Ⅳ)和钒(Ⅴ)可定量地萃入氯仿中。对有机层进行测定,钒(Ⅳ)和钒(Ⅴ)分别在345和350nm处显示出最大的吸收。对钒(Ⅳ)在350nm波长处的行为也进行了研究。在380nm以外,钒(Ⅴ)吸收仍相当大,但是,钒(Ⅳ)在这范围内的吸收可忽略不计。对于钒(Ⅳ)和钒(Ⅴ)两种离子来说,即使4天以后,有机层的吸收也不会变化的。采用“Job”法测得所形成的络合物的组成比已确定为1:2(金属;配位体)。对于钒(Ⅳ)如钒(Ⅴ)的测定进行干扰研究,并提出了消除外来离子干扰的方法。在pH4条件下,钒(Ⅳ)和钒(Ⅴ)可定量地萃取;这种萃取法成功地用于同时测定1—3 μgmL^-1范围的钒(Ⅳ)和1—6μgmL^-1范围的钒(Ⅴ),分别在350nm和400nm测量其吸收。

关键词：钒萃取测定

Potential impact of combined inhibition of 3a-oxidoreductases and 5a-reductases on prostate cancer

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Asian Journal of Urology 2019年第1期6卷 50-56页

作者： Michael v.Fiandalo Daniel T.gewirth James L.Mohler Department of Urology Roswell Park Comprehensive Cancer CenterBuffaloNYUSA Hauptman-Woodward Medical Research Institute BuffaloNYUSA

Prostate cancer(PCa)growth and progression rely on the interaction between the androgen receptor(AR)and the testicular ligands,testosterone and dihydrotestosterone(DHT).Almost all men with advanced PCa receive androgen deprivation therapy(ADT).ADT lowers circulating testosterone levels,which impairs AR activation and leads to PCa ***,ADT is palliative and PCa recurs as castration-recurrent/resistant PCa(CRPC).One mechanism for PCa recurrence relies on intratumoral synthesis of DHT,which can be synthesized using the frontdoor or primary or secondary backdoor *** metabolism inhibitors,such as those targeting 5a-reductase,aldo-keto-reductase family member 3(AKR1C3),or cytochrome P45017A1(CYP17A1)have either failed or produced only modest clinical *** goal of this review is to describe the therapeutic potential of combined inhibition of 5a-reductase and 3a-oxidoreductase enzymes that facilitate the terminal steps of the frontdoor and primary and secondary backdoor pathways for DHT *** of the terminal steps of the androgen metabolism pathways may be a way to overcome the shortcomings of existing androgen metabolism inhibitors and thereby delay PCa recurrence during ADT or enhance the response of CRPC to androgen axis manipulation.

关键词： Androstanediol Dihydrotestosterone Dutasteride 3a-oxidoreductases Androgen deprivation therapy Abiraterone

Neuropsychopharmacological profile of Astragalus membranaceous ***

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Journal of Traditional Chinese Medical Sciences 2019年第3期6卷 254-262页

作者： Aldarmaa Jalsrai Avijit Biswas Nikolai I.Suslov Joseph v.Martin Institute of Traditional Medicine and Technology 495 Ulaanbaatar-36Mongolia Biology Department Rutgers University315 Penn St.CamdenNJ 08102USA Research Institute of Pharmacology and Regenerative Medicine 3 Lenin Ave.Tomsk 634028Russia Center for Computational and Integrative Biology Rutgers UniversityCamdenNJ 08102USA

Objective:To clarify the neuropharmacological profile of the Mongolian vetch,Astragalus mongholicus(Astragalus membranaceous ***;synonym:***),extracts were evaluated for behavioral effects in rats and ***:An aqueous extract of *** was made by boiling roots from freshlycollected plants in 2.5 volumes(w/v)of water for 60 *** ethanol extract was made by incubating in 70%ethanol for 5 days at 25*** of the aqueous extracts were evaluated in a forced swimming assessment of antidepressant effects,a hole-board test of exploratory behavior,an analysis of inhibition of aggression following electrical stimulation and influences on amnesia resulting from ***,effects of ethanol extracts of *** were assessed on L-tryptophan induced twitches(indicating serotonin-mediated effects)and on hypothermia induced by apomorphine(indicating dopamine-mediated interactions)in ***:Per os(PO)administration of the aqueous decoction of the vetch to rats increased the response in a forced swimming test as reflected in wheel ***,the decoction had no significant effect on the exploratory behavior of rats in the hole-board *** PO administration of the aqueous extract of *** decreased the threshold for aggressive behavior and this effect persisted with subchronic *** administration of the plant extract suppressed aggression of *** ethanol extract of *** showed an antiserotoninergic action and had a significant influence on the hypothermia induced by ***:*** has a variety of potent psychotropic actions,suggesting influences on diverse neurotransmitter systems.

关键词： Antidepressant Anxiolytic Mongolian vetch Nootropic Psychotropic effect

Two-photon physics at future electron-positron colliders

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Chinese Physics C 2023年第1期47卷 7-18页

作者： I.R.Boyko v.v.Bytev A.S.Zhemchugov Joint Institute for Nuclear Research DubnaRussia

Two photon collisions offer a variety of physics phenomena that can be studied at future electronpositron *** the planned CEPC parameters as a benchmark,we consider several topics within twophoton *** the full integrated luminosity,Higgs boson photoproduction can be reliably observed,and large statistics on various quarkonium states can be *** LEP results for the photon structure function and tau lepton anomalous magnetic moment can be improved by 1-2 orders of magnitude.

关键词： future colliders two-photon physics Higgs boson

在vEPP-2000正负电子对撞机上寻找η'→e^+e^-和η→e^+e^-（英文）

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中国科学技术大学学报 2016年第6期46卷 528-532页

作者： KARDAPOLTSEv L.v. 无俄罗斯布德克尔核物理研究所俄罗斯新西伯利亚630090 国立新西伯利亚大学俄罗斯新西伯利亚630090 SND合作组

在vEPP-2000正负电子对撞机上,用SND探测器研究了稀有衰变η'→e^+e^-,研究中使用了逆过程e^+e^-→η'和η'的五个衰变链.90%的置信度的Γη'→e^+e^-上限被设定为0.002 e v;还研究了用SND寻找η→e^+e^-过程的灵敏度,为此分析了质心能... 详细信息

在vEPP-2000正负电子对撞机上,用SND探测器研究了稀有衰变η'→e^+e^-,研究中使用了逆过程e^+e^-→η'和η'的五个衰变链.90%的置信度的Γη'→e^+e^-上限被设定为0.002 e v;还研究了用SND寻找η→e^+e^-过程的灵敏度,为此分析了质心能量520-580 Me v之间积分亮度为108 nb-1的数据,没有发现当η→π~0π~0π0时,衰变e^+e^-→η过程的本底事例.在无本底情况下,vEPP-2000运行两周时B(η→e^+e^-)灵敏度即可达到10^(-6).

关键词： vEPP-2000 SND 正负电子电子分宽度