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Negative thermal expansion in one-dimension of a new double sulfate AgHo(sO_(4))_(2)with isolated sO_4 tetrahedra

Journal of Materials science & Technology 2021年第17期76卷 111-121页

作者： Yuriy G.Denisenko Victor V.Atuchin Maxim s.Molokeev Naizheng Wang Xingxing Jiang Aleksandr s.Aleksandrovsky alexander s.Krylov Aleksandr s.Oreshonkov alexander E.sedykh svetlana s.Volkova Zheshuai Lin Oleg V.Andreev Klaus Müller-Buschbaum Institute of Chemistry Tyumen State University.Tyumen625003Russia Institute of Inorganic and Analytical Chemistry Justus-Liebig-University of Giessen35392Giessen.Germany Department of General and special Chemistry Industrial University of TyumenTyumen625000Russia Laboratory of Optical Materials and structures Institute of Semiconductor PhysicsSB RASNovosibirsk630090Russia Laboratory of semiconductor and Dielectric Materials Novosibirsk State UniversityNovosibirsk630090Russia Research and Development Department.Kemerovo state University Kemerovo650000Russia Laboratory of Crystal Physics Kirensky Institute of PhysicsFederal Research Center KSC SB RASKrasnoyarsk660036Russia siberian Federal University Krasnoyarsk660041Russia Department of Physics Far Eastern State Transport UniversityKhabarovsk680021Russia Technical Institute of Physics and Chemistry Chinese Academy of SciencesBeijing100190China Laboratory of Coherent Optics Kirensky Institute of Physics.Federal Research Center KSC SB RASKrasnoyarsk660036Russia Institute of Nanotechnology Spectroscopy and Quantum ChemistrySiberian Federal UniversityKrasnoyarsk660041Russia Laboratory of Molecular spectroscopy Kirensky Institute of PhysicsFederal Research Center KSC SB RASKrasnoyarsk660036Russia Center for Materials Research(LaMa) Justus-Liebig-University GiessenGiessen35392Germany University of the Chinese Academy of sciences Beijing100049China Laboratory of the Chemistry of Rare Earth Compounds Institute of Solid State ChemistryUB RASEkaterinburg620137Russia

A double holmium-silver sulfate was obtained for the first *** temperature intervals for the formation and stability of the compound were determined by differential scanning *** crystal structure of AgHo(sO_(4))_(2)was determined by Rietveld *** X-ray diffraction(XRD)analysis showed that the compound crystallizes in the monoclinic syngony,space group P2_1/m,with the unit cell parameters a=4.71751(4)A,b=6.84940(6)A and c=9.89528(9)A,β=95.1466(4)·,V=318.448(5)A^(3),Z=2,R_B=1.55%,T=303 *** types of sulfate tetrahedra were found in the structure,which significantly affected the spectral properties in the infrared *** the temperature range of 143-703 K,a negative thermal expansion along the b direction accompanied by a positive thermal expansion along the a and c directions was *** was established that negative thermal expansion is the result of the deformation of sulfate tetrahedra,which is affected by the movement of holmium and silver *** excitation in the blue spectral range(457.9 nm)produces a luminescence in light blue(489 nm),green(545 nm)and red(654 nm)spectral ranges,and the latter two were of comparable intensity that is favorable for WLED *** observed luminescent band distribution is ascribed to the specific crystal field at Ho^(3+)ion sites rather than a variation of radiationless probability.

关键词： sulfate Crystal structure Thermal expansion Raman Photoluminescence Band structure

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Theory of superfluidity and drag force in the one-dimensional Bose gas

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Frontiers of physics 2012年第1期7卷 54-71页

作者： alexander Yu. Cherny (1) Jean-sébastien Caux (2) Joachim Brand (3) 1. Bogoliubov Laboratory of Theoretical Physics Joint Institute for Nuclear Research 141980 Dubna Moscow region Russia2. Institute for Theoretical Physics Science Park 904 University of Amsterdam 1090 GL Amsterdam The Netherlands3. Centre for Theoretical Chemistry and Physics and New Zealand Institute for Advanced Study Massey University Private Bag 102904 North Shore Auckland 0745 New Zealand

The one-dimensional Bose gas is an unusual superfluid. In contrast to higher spatial dimensions, the existence of non-classical rotational inertia is not directly linked to the dissipationless motion of infinitesimal impurities. Recently, experimental tests with ultracold atoms have begun and quanti- tative predictions for the drag force experienced by moving obstacles have become available. This topical review discusses the drag force obtained from linear response theory in relation to Lan- dau＇s criterion of superfluidity. Based upon improved analytical and numerical understanding of the dynamical structure factor, results for different obstacle potentials are obtained, including single impurities, optical lattices and random potentials generated from speckle patterns. The dynamical breakdown of superfluidity in random potentials is discussed in relation to Anderson localization and the predicted superfluid-insulator transition in these systems.

关键词： Lieb-Liniger model Tonks-Girardeau gas Luttinger liquid drag force superfluidity,dynamical structure factor

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Pancreatic head cancer in a patient with complete agenesis of dorsal pancreas

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Hepatobiliary surgery and Nutrition 2019年第3期8卷 327-328页

作者： alexander E.Julianov Azize s.saroglu Department of surgery Trakia HospitalStara ZagoraBulgaria

A previously healthy 65-year-old female patient was admitted to our hospital due to painless obstructive jaundice of 1 week *** investigation showed elevated serum bilirubin,alkaline phosphatase and gamma-glutamyl transferase levels,with no other significant abnormalities.A contrast-enhanced computed tomography revealed a hypovascular lesion in the head of the pancreas(arrow,panel A),with an absence of body and tail of the gland near the splenic vessels(arrows,panel B).

关键词： pancreas admitted patient

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激光辐射波长和脉冲寿命对碲化镉熔化阈值的影响

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材料导报 2024年第7期38卷 40-45页

作者：列维茨基·谢尔盖曹泽祥柯巴·亚历山大柯巴·玛丽亚乌克兰国家科学院半导体物理研究所基辅03028 乌克兰国立技术大学物理技术学院基辅03058 乌克兰国民警卫研究所国家安全系基辅03028

碲化镉的相对分子量为240,密度为5.885 g/cm^(3),熔点为1092℃。碲化镉是一种Ⅱ-Ⅵ族的化合物半导体材料,属于直接带隙型,带隙宽度为1.56 eV。碲化镉是制造X射线、伽马射线和红外线探测器的基本材料。对碲化镉的特别关注主要是由于其大... 详细信息

碲化镉的相对分子量为240,密度为5.885 g/cm^(3),熔点为1092℃。碲化镉是一种Ⅱ-Ⅵ族的化合物半导体材料,属于直接带隙型,带隙宽度为1.56 eV。碲化镉是制造X射线、伽马射线和红外线探测器的基本材料。对碲化镉的特别关注主要是由于其大原子数和大的光电吸收截面。在基于CdTe的伽马辐射势垒探测器结构中,其表面的处理方法之一是纳秒激光照射,在某些情况下,纳秒激光照射可以在触点(Ag、In、Au)和势垒形成的技术处理阶段优化所需的表面参数。另一种方法是在脉冲激光照射下在碲化镉表面形成有序的纳米结构。对基于半导体及其结构的脉冲激光器,可根据其不同的脉冲持续时间τ_(p)和辐射波长λ将其分类。例如,红宝石激光器(λ=694 nm)、钕激光器(一次谐波1064 nm和两次谐波532 nm)、准分子KrF激光器(248 nm)和XeF激光器(351 nm)等,其脉冲持续时间分别为7、20、80、120 ns。这些激光器常被应用于表面修饰等领域。因此,往往有必要事先知道或至少估计在脉冲激光辐射下碲化镉表面的熔化温度和阈值,这取决于激光脉冲持续时间τ_(p)、辐射波长(光吸收系数α(λ))以及碲化镉表面本身的电物理参数,特别是表面重组率s和非平衡电荷载流子的寿命。这些参数取决于表面处理的方法和掺杂物的浓度。在上述情况下,实验研究是非常耗费人力和时间的,因此基于τ_(p)、α(λ)和碲化镉表面本身的电物理参数对融化阈值th和表面温度进行理论计算变得非常重要。本工作采用激光照射碲化镉,辐射波长为300~800 nm,脉冲持续时间为7~120 ns。为了以非破坏性的和有效的方法来管理接近表面层状态的CdTe,在T=80 K下进行了光致发光实验。为了监测熔化阈值,研究了由Acrorad公司制造和抛光的尺寸为5 mm×5 mm×0.5 mm的Cl补偿p-CdTe(111)单晶的光致发光光谱。经过研究发现,在激光脉冲寿命从7ns到1μs的范围内,CdTe熔化阈值明显取决于光吸收系数α(λ)。因为在脉冲寿命长于1μs的情况下,热扩散深度明显大于CdTe中的激光辐射穿透深度,并开始依赖于反射系数R(λ)。对于较短的激光脉冲长度τ_(p),当辐射波长λ变化时,熔化阈值会发生显著变化。同时,非平衡过剩载流子参数的变化(如表面重组速度s从10^(3)m/s增加到10^(5)m/s,还有扩散深度LD从0.4μm增加到2μm)会对CdTe熔化阈值产生至少25%的影响。而且红宝石激光的脉冲持续时间在(20±5)ns区间内的变化导致相对熔化阈值的变化(ΔIth/Ith)为35%。CdTe熔化阈值的计算值可以有效地被用于优化脉冲激光对晶体的表面处理与掺杂。

关键词：碲化镉熔化阈值脉冲激光辐照半导体激光掺杂

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Effect of electron injection in copper-contacted graphene nanoribbons

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Nano Research 2016年第9期9卷 2735-2746页

作者： Konstantin A.simonov Nikolay A.Vinogradov alexander s.Vinogradov alexander V.Generalov Gleb I.svirskiy Attilio A.Cafolla Nils Martensson Alexei B. Preobrajenski Department of Physics and Astronomy Uppsala UniversityUppsala Box 51675120Sweden MAX Ⅳ Laboratory Lund UniversityLund Box 11822100Sweden V.A.Fock Institute of Physics St.Petersburg State UniversitySt.Petersburg 198504Russia school of Physical sciences Dublin City UniversityDublin 9Ireland

For practical electronic device applications of graphene nanoribbons (GNRs), it is essential to have abrupt and well-defined contacts between the ribbon and the adjacent metal lead. By analogy with graphene, these contacts can induce electron or hole doping, which may significantly affect the I/V characteristics of the device. Cu is among the most popular metals of choice for contact materials. In this study, we investigate the effect of in situ intercalation of Cu on the electronic structure of atomically precise, spatially aligned armchair GNRs of width N = 7 (7-AGNRs) fabricated via a bottom-up method on the Au(788) surface. scanning tunneling microscopy data reveal that the complete intercalation of about one monolayer of Cu under 7-AGNRs can be facilitated by gentle annealing of the sample at 80 °C. Angle-resolved photoemission spectroscopy (ARPEs) data clearly reflect the one-dimensional character of the 7-AGNR band dispersion before and after intercalation. Moreover, ARPEs and core-level photoemission results show that intercalation of Cu leads to significant electron injection into the nanoribbons, which causes a pronounced downshift of the valence and conduction bands of the GNR with respect to the Fermi energy (ΔE ~ 0.5 eV). As demonstrated by ARPEs and X-ray absorption spectroscopy measurements, the effect of Cu intercalation is restricted to n-doping only, without considerable modification of the band structure of the GNRs. Post-annealing of the 7-AGNRs/Cu/Au(788) system at 200 °C activates the diffusion of Cu into Au and the formation of a Cu-rich surface Au layer. Alloying of intercalated Cu leads to the recovery of the initial position of GNR-related bands with respect to the Fermi energy (E sub>Fsub>), thus, proving the tunability of the induced n-doping.

关键词： graphene nanoribbons bottom-up method copper intercalation charge injection angle-resolved photoemission spectroscopy (ARPEs) scanning tunneling microscopy

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spatial Industrial Accident Exposure and social Vulnerability Assessment of Hazardous Material sites,Chemical Parks,and Nuclear Power Plants in Germany

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International Journal of Disaster Risk science 2023年第2期14卷 223-236页

作者： alexander Fekete steffen Neuner Institute of Rescue Engineering and Civil Protection TH Köln-University of Applied Sciences50679CologneGermany

Industrial accidents have shown that many people can be affected,such as in seveso,Italy,in *** accidents in nuclear power plants have also led to fatalities and *** better guide preparedness against and mitigation of industrial accidents,an assessment is necessary to evaluate hazard exposure and the type of potentially vulnerable social groups that need to be taken into *** study conducted a spatial assessment of three types of industrial facilities in Germany:facilities registered under the seveso Directive,chemical parks,and nuclear power *** method consisted of a spatial assessment using a Geographic Information system of exposure around hazardous sites registered under the s eveso Directive in Germany and of census data to analyze social *** analyzed included industrial accidents and *** results revealed that most industrial sites are in urban areas and that population density,the numbers of foreigners,and smaller housing unit sizes are higher in close proximity to these *** buffer zones analyzed in circles between 1 and 40 km show a decreasing vulnerability with more *** can guide emergency management planners and other stakeholders to better prepare for major accidents and better devise disaster risk reduction strategies specifically for different social groups.

关键词： Germany Industrial disaster risk seveso directives seveso sites social vulnerability

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Alkali-thermal gasification and hydrogen generation potential of biomass

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Frontiers of Chemical science and Engineering 2017年第3期11卷 369-378页

作者： alexander B. Koven shitang s. Tong Ramin R. Farnood Charles Q. Jia Department of Chemical Engineering and Applied Chemistry University of Toronto Ontario M5S-3E5 Canada school of Chemistry and Chemical Engineering Wuhan University of Science and Technology Wuhan 430081 China

Generating hydrogen gas from biomass is one approach to lowering dependencies on fossil fuels for energy and chemical feedstock, as well as reducing greenhouse gas emissions. Using both equilibrium simulations and batch experiments with NaOH as a model alkaline, this study established the technical feasibility of converting various biomasses （e.g., glucose, cellulose, xylan and lignin） into H2-rich gas via catalyst-free, alkali-thermal gasification at moderate temperatures （as low as 300℃）. This process could produce more H2 with less carbon-containing gases in the product than other comparable methods. It was shown that alkali-thermal gasification follows CxHyO2 ＋ 2xNaOH ＋（x-z）H20 = （2x＋y/2-z）H2 ＋xNa2CO3, with carbonate being the solid product which is different from the one suggested in the literature. Moreover, the concept of hydrogen genera- tion potential （H2-GP）-the maximum amount of H2 that a biomass can yield, was introduced. For a given biomass CxHyO2, the H2-GP would be （2x ＋ y/2-z） moles of H2. It was demonstrated experimentally that the H2-GP was achievable by adjusting the amounts of H20 and NaOH, temperature and pressure. Keywords hydrogen generation potential, biomass, lignocellulose, alkali-thermal gasification, sodium hydroxide

关键词： hydrogen generation potential biomass lignocellulose alkali-thermal gasification sodium hydroxide

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Evaluation and management of the child with hypothyroidism

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World Journal of Pediatrics 2019年第2期15卷 124-134页

作者： alexander K.C.Leung alexander A.C.Leung Department of Pediatrics The University of Calgaryand The Alberta Children's Hospital#200233-16th Avenue NWCalgaryAB T2M 0H5Canada Department of Medicine The University of CalgaryCalgaryABCanada

Background Thyroid hormones are critical for early neurocognitive development as well as growth and development throughout *** recognition and treatment of hypothyroidism is,therefore,of utmost importance to optimize physical and neurodevelopmental *** sources A PubMed search was completed in Clinical Queries using the key terms 'hypothyroidism'.Results Hypothyroidism may be present at birth (congenital hypothyroidism) or develop later in life (acquired hypothyroidism).Thyroid dysgenesis and dyshormonogenesis account for approximately 85% and 15% of permanent cases of congenital primary hypothyroidism,*** than 95% of infants with congenital hypothyroidism have few,if any,clinical manifestations of *** screening programs allow early detection of congenital *** developed countries,Hashimoto thyroiditis is the most common cause of goiter and acquired hypothyroidism in children and ***,iodine deficiency associated with goiter is the most common cause of *** hypothyroidism is uncommon and may be associated with other congenital syndromes and deficiencies of other pituitary *** of the clinical features would allow prompt diagnosis and institution of *** To optimize neurocognitive outcome in infants with congenital hypothyroidism,treatment with levothyroxine should be started as soon as possible,preferably within the first 2 weeks of *** with acquired hypothyroidism should also be treated early to ensure normal growth and development as well as cognitive *** target is to keep serum TsH serum free T4 or total T4 within the upper half of the age-specific reference range,with elimination of all symptoms and signs of hypothyroidism.

关键词： Dysgenesis Dyshormonogenesis Hashimoto thyroiditis Hypothyroidism Iodine deficiency Levothyroxine Mental retardation stunted growth

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Nonalcoholic fatty liver disease is associated with benign gastrointestinal disorders

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World Journal of Gastroenterology 2013年第45期19卷 8301-8311页

作者： srinevas K Reddy Min Zhan H Richard alexander samer s El-Kamary Department of surgery University of Maryland School of Medicine BaltimoreMD 21201 United States Department of Epidemiology and Public Health University of Maryland School of Medicine Baltimore MD 21201United States Departments of Pediatrics Epidemiology and Public Health University of Maryland School of MedicineBaltimore MD 21201 United States

AIM:To explore associations between nonalcoholic fatty liver disease(NAFLD)and benign gastrointestinal and pancreato-biliary ***:Patient demographics,diagnoses,and hospital outcomes from the 2010 Nationwide Inpatient sample were *** liver diseases were identified using International Classification of Diseases,the 9thRevision,Clinical Modification *** with NAFLD were compared to those with other chronic liver diseases for the endpoints of total hospital charges,disease severity,and hospital *** stepwise logistic regression analyses to assess for the independent association of demographic,comorbidity,and diagnosis variables with the event of NAFLD(vs other chronic liver diseases)were also ***:Of 7800441 discharge records,32347(0.4%)and 271049(3.5%)included diagnoses of NAFLD and other chronic liver diseases,*** patients were younger(average 52.3 years vs55.3 years),more often female(58.8%vs 41.6%),less often black(9.6%vs 18.6%),and were from higher income areas(23.7%vs 17.7%)compared to counterparts with other chronic liver diseases(all Ps mellitus(43.4%vs 28.9%),hypertension(56.9%vs 47.6%),morbid obesity(36.9%vs 8.0%),dyslipidemia(37.9%vs 15.6%),and the metabolic syndrome(28.75%vs 8.8%)were all more common among NAFLD patients(all Pspital charge($39607 vs$51665),disease severity scores,and intra-hospital mortality(0.9%vs6.0%)were lower among NALFD patients compared to those with other chronic liver diseases(all Pseases,NAFLD was significantly associated with diverticular disorders[OR=4.26(3.89-4.67)],inflammatory bowel diseases[OR=3.64(3.10-4.28)],gallstone related diseases[OR=3.59(3.40-3.79)],and benign pancreatitis[OR=2.95(2.79-3.12)]on multivariable logistic regression(all Psorders were the principal diagnoses on hospital *** relationships were observ

关键词： Nationwide inpatient sample Nonalcoholic fatty liver disease Chronic liver disease Diverticular disease Pancreatitis Gallstones Inflammatory bowel disease

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Increased paracellular permeability of tumor-adjacent areas in 1,2-dimethylhydrazine-induced colon carcinogenesis in rats

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Cancer Biology & Medicine 2018年第3期15卷 251-259页

作者： Viktoria V.Bekusova Evgeny L.Falchuk Larisa s.Okorokova Natalia M.Kruglova alexander D.Nozdrachev alexander G.Markov Department of Physiology St.Petersburg State University I.P.Pavlov Institute of Physiology Russian Academy of Sciences

Objective: The morphology and functions of the proximal and distal large intestine are not the same. The incidence of colorectal cancer in these regions is also different, as tumors more often appear in the descending colon than in the ascending *** bowel disease and colorectal cancer can increase transepithelial permeability, which is a sign of reduced intestinal barrier function. However, there is not enough evidence to establish a connection between the difference in colorectal cancer incidence in the proximal and distal colon and intestinal permeability or the effects of carcinogenesis on the barrier properties in various areas of the colon. The aim of the study was to assess the permeability of different segments of the large intestine according to a developed mapping methodology in healthy rats and rats with 1,2-dimethylhydrazine(DMH)-induced colon ***: The short circuit current, the transepithelial electrical resistance and the paracellular permeability to fluorescein of large intestine wall of male Wistar rats were examined in the Ussing chambers. The optical density of the solution from the serosa side to assess the concentration of the diffused fluorescein from mucosa to serosa was analyzed by spectrophotometry. The morphometric and histological studies were performed by optical ***: Rats with DMH-induced colon adenocarcinomas showed elevated transepithelial electrical resistance in the areas of neoplasm development. In contrast, there was no change in the electrophysiological properties of tumor adjacent areas, however,the paracellular permeability of these areas to fluorescein was increased compared to the control rats and was characterized by sharply reduced barrier ***: The barrier properties of the colon vary depending on tumor location. The tumors were less permeable than the intact intestinal wall and probably have a negative influence on tumor-adjacent tissues by disrupting their bar

关键词： Rat 1,2-dimethylhydrazine colorectal cancer Ussing chamber short circuit current transepithelial electrical resistance intestinal permeability

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