bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Terpenes and Terpenoids of Natural Occurrence in Essential Oils on Vascular Smooth Muscle and on Systemic Blood Pressure: Pharmacological Studies and Perspective of Therapeutic Use
Authors: Carolina Cardoso-Teixeira Ana , Oliveira-Abreu Klausen , Gabriel de Freitas Brito Levy , Noronha Coelho-de-Souza Andrelina , Henrique Leal-Cardoso José
Published: November 2020

Terpenes are a class of chemical compounds with carbon and hydrogen atoms in their structure. They can be classified into several classes according to the quantity of isoprene units present in its structure. Terpenes can have their structure modified by the addition of various chemical radicals. When these molecules are modified by the addition of atoms other than carbon and hydrogen, they become terpenoids. Terpenes and terpenoids come from the secondary metabolism of several plants. They can be found in the leaves, fruits, stem, flowers, and roots. The concentration of terpenes and terpenoids in these organs can vary according to several factors such as the season, collection method, and time of the day. Several biological activities and physiological actions are attributed to terpenes and terpenoids. Studies in the literature demonstrate that these molecules have antioxidant, anticarcinogenic, anti-inflammatory, antinociceptive, antispasmodic, and antidiabetogenic activities. Additionally, repellent and gastroprotective activity is reported. Among the most prominent activities of monoterpenes and monoterpenoids are those on the cardiovascular system. Reports on literature reveal the potential effect of monoterpenes and monoterpenoids on systemic blood pressure. Studies show that these substances have a hypotensive and bradycardic effect. In addition, the inotropic activity, both positive and negative, of these compounds has been reported. Studies also have shown that some monoterpenes and monoterpenoids also have a vasorelaxing activity on several vascular beds. These effects are attributed, in many cases to the blocking of ion channels, such as voltage-gated calcium channels. It can also be observed that monoterpenes and monoterpenoids can have their effects modulated by the action of the vascular endothelium. In addition, it has been shown that the molecular structure and the presence of chemical groups influence the potency and efficacy of these compounds on vascular beds. Here, the effect of several monoterpenes and monoterpenoids on systemic blood pressure and vascular smooth muscle will be reported.
Nonresectional-Graded Neo Chordal Dynamic Repair of Mitral Valve: Stress Analysis Induced Surgical Innovation
Authors: Kumar Radhakrishnan Pradeep , Ananyajyothi Ambat Gayathri , Nazer Nihas , Yoosuf Abdul Nazer
Published: November 2020

Drawbacks persist relating to irreversibility of leaflet resection, time-consuming leaflet reconstruction with sliding annuloplasty, monoleaflet function, and systolic anterior motion (SAM) risk. Graded neochordal reconstruction mitigates many of these but has the challenge of precise sizing and possibility of leaving excessive tissue, risking SAM. When this reconstruction is based on stress analysis and shear analysis methods the outcome gives the best results. Short term evaluation has been done with good outcomes.
A Novel Drug Delivery System Based on Nanoparticles of Magnetite Fe3O4 Embedded in an Auto Cross-Linked Chitosan
Authors: Fouad Damiri , Bachra Yahya , Ayoub Grouli , Ouaket Amine , Bennamara Ahmed , Knouzi Noureddine , Berrada Mohammed
Published: November 2020

Recently, chitosan (CS) was given much attention as a functional biopolymer for designing various hydrogels for industrial, environmental and biomedical applications, but their biomedical use is limited due to the toxicity of the crosslinker agents. To overcome this inconvenience, we developed an auto cross-linked material based on a chitosan backbone that carries an amino and aldehyde moieties. This new drug delivery system (DDS) was designed by using oxidized chitosan (OCS) that crosslinks chitosan (CS). In the first part, a simple, rapid, low-cost and eco-friendly green method was introduced to synthesize magnetite nanoparticles (Fe3O4-NPs) successfully. These nanoparticles Fe3O4 have received a great deal of attention in the biomedical field. Especially in a targeted drug delivery system, drug-loaded Fe3O4-NPs can accumulate at the tumor site by the aid of an external magnetic field and increase the effectiveness of drug release to the tumor site. In the second part, we have incorporated the Fe3O4-NPs into chitosan/oxidized chitosan solution because of their unique magnetic properties, outstanding magnetism, biocompatibility, lower toxicity, biodegradability, and other features. Three drugs (5-Fluorouracil (5-FU), Caffeine and Ascorbic acid)) were embedded into the magnetite solution that became quickly a hydrogel. The successful fabrication of the hydrogels and ferrogels was confirmed by (FT-IR), (TGA), (SEM), (VSM) analysis at room temperature. Finally, results showed that our hydrogels and ferrogels may be technologically used as devices for drug delivery in a controllable manner.
Italian Crisis Management in 2020
Authors: Franchina Luisa , Calabrese Alessandro , Scatto Enrico , Inzerilli Giulia
Published: November 2020

Approaches to risk analysis, crisis management and resilience enhancement for Critical Infrastructure (CI) Protection will be considered starting from a case study related to the management of the pandemic in Italy. Business continuity and crisis management models for CI are analyzed aiming to deal with complexity and reduce uncertainty relating pandemic and long-time crisis. Furthermore, is presented a methodology highlighting the functioning of the Italian Civil Protection and its systemic nature: a complex apparatus made up of different elements and organizations, which derives from the functioning of different organizational systems in interaction with each other. As a baseline for the coordination management the Augustus Method is considered for its strategical, tactical and operational aspects. One of the main outputs of the research consists in creating a “what if” forecasting model, configured as a visualization of the propagation of negative effects on the supply chain and manpower over time.
The Comparative Historical Analysis of Education Systems in the Czech Republic and Kazakhstan (1990–2000)
Authors: Vaculík Jaroslav , Satanov Arstan
Published: November 2020

The objective of the article is to examine patterns of similarities and differences across educational reforms in the Czech Republic and Kazakhstan in post-socialist context. The study conducted a comparative-historical analysis of the development of education systems in Kazakhstan and the Czech Republic in the 1990s when there was a transition of these countries from the socialist to the capitalist regime. The comparative historical analysis of the educational reforms of these two countries identified a number of similar patterns and considerable differences in the development of their education systems due to many contextual and structural factors and historical prerequisites. The comparative analysis demonstrated that both in the educational systems of the Czech Republic and Kazakhstan democratization, humanization and differentiation were taken as main principles of the reforms, but these processes developed in different levels and directions. As a result, it was stated that both the Czech Republic and Kazakhstan intended to democratize educational systems in the post-socialist context. While the Czech Republic tended to decentralize and diversify the school system, delegating the practical implementation of educational policies to various organizations and lobbying groups, however, Kazakhstan maintains a highly centralized system from top to bottom, which leaves little administrative, financial, managerial, executive authority for the low structures of the state apparatus and the public, which limits the system to strict planning and standards.
Social Work in the Czech Republic – Origin and Role in Education
Authors: Gulová Lenka , Střelec Stanislav
Published: November 2020

Social work is often surrounded by misconceptions and even contradictions. Over the course of history, social work has become an integral part of living in modern society. It is our goal to describe this phenomenon in this paper. We discuss the origin, content, and processes involved in social work in our country over the course of the past century. At the end we present the results of a research project focused on the support of socially disadvantaged Roma groups by means of educational programmes that help to improve their study, work, and life prospects.
Real Gymnasium and its Importance in the Context of Rebirth of Poland in 1918 – Poznan Case
Authors: Gulczyńska Justyna
Published: November 2020

The subject of the article is the real gymnasium and its implementation in Poland after the restoration of its independence in 1918. Real gymnasium is a type of institutional education, functioning in the nineteenth and the beginning of the twentieth century. It was a secondary general education school that typically emphasizes mathematics and natural sciences. Its goal was to educate in a practical, useful and polytechnic spirit. This type of school was developed in Poland under Prussian partition, but also since Poland’s independence.
Is the Name “Polish Death Camps” a Misnomer?
Authors: Gancarson Jacek , Zaitceva Natalia
Published: November 2020

The purpose of the study is a historical-linguistic analysis of the ambiguous name “Polish death camps” (or “Polish concentration camps”), which for the last thirty years has led to conflicting assessments among politicians, journalists and historians, and in some cases being considered as a term. In order to make an accurate assessment of this name, and to clarify the question of the correctness/incorrectness of its use and come to a conclusion about the linguistic suitability/unsuitability to consider it a term, the authors study the new evidence by historians, interviews with public and political figures, and in particular, for the first time investigate the original editorial material where the name was formulated. In the course of the study, the true source of the name “Polish death camps” was first disclosed and a comprehensive history of its use was presented. Basing on gathered material the conclusion was made that the name is linguistically incorrect and can not be used as a term.
The Cooperative as a Form of Education in the Theory and Practice of the Work of Women’s Organisations in the Second Republic of Poland, as Exemplified by the Women’s Social Self-Help Association
Authors: Piwowarczyk Mirosław
Published: November 2020

The work of the SSK was integrally and consistently a part of the social and economic life of the 1930s in the Interwar Period in Poland. It was clearly ideologically oriented. By uniting women and promoting their activity the association served a supportive and educational role for hundreds of Polish women and families. Although the scope of the work of the organisation was not particularly broad, through the realisation of the ideas and the implementation of the form of the cooperative, the association contributed to the increase of the level of life of numerous Polish women in its social, economic, and cultural aspects.
Situation in Subcarpathian Rus in 1919 as Reported By the Czech Officials
Authors: Shevchenko Kirill
Published: November 2020

The article focuses on various aspects of the situation in Subcarpathian Rus raised and analyzed in the reports of the Czech officials, who visited the Subcarpathian region during 1919. Most Czech officials stated the vital need for a far-sighted and responsible policy in this strategically important region. In their reports to Prague, most Czech officials divided the local Rusyn intelligentsia in Subcarpathian Rus into pro-Russian and local orientations, and recommended Czechoslovak authorities to rely on and to provide support for the representatives of the local orientation as more preferable for Prague interests in that region.
The Role of Professor Władysław Semkowicz and the Jagiellonian University in Promoting Polonophilia in Slovakia in the Interwar Period
Authors: Matula Pavol
Published: November 2020

The interwar relations between Czechoslovakia and Poland were tense for almost twenty years. Problems were caused not only by border disputes. In this situation, the interest of young Slovak intelligence in Polish culture and science began to increase in the early 1920s, which was supported by Warsaw, in its efforts to undermine the position of Prague. A well-known Slovakophile, Professor Władysław Semkowicz played an important role in supporting young Slovaks. His largest impact on Slovak-Polish relations was his patronage of visiting Slovak students at the Jagiellonian University. Semkowicz’s efforts gradually bore fruit. Many of the programme participants promoted Polish literature, art and history after their return home. This Polonophilia was not limited to the cultural sphere but also had an effect on politics. At the end of 1938, the Polish territorial claims against Slovakia severely disappointed the Polonophiles. Nevertheless, there were a number of Slovaks who kept their contacts in Polish cultural circles and continued to have pro-Polish sentiments even after the country’s defeat in September 1939.
Raně středověké říční koryto v blízkosti fortifikačního systému velkomoravského hradiska Pohansko u Břeclavi
Authors: Nehyba Slavomir , Dresler Petr , Doláková Nela , Kuda František , Přišťáková Michaela , Šimík Jakub , Škojec Jaroslav , Kirchner Karel
Published: November 2020

Geophysical, sedimentological, palynological, absolute-age dating and archeological techniques were used to study the deposits of the Early Medieval fluvial channel in the area of the Great Moravia Empire agglomeration Pohansko near Břeclav. Artificial profile situated on the base of ERT profiles and the archeological results led to opening of the fluvial channel. Newly documented fluvial channel erosively cut the complex of flood loams. Gravel lag covers the bottom of the channel and grade upwards into sandy channel infill with fining upward trend. Fluvial sandy dunes forming the most characteristic architectural element of the infill are represented mostly by trough cross-stratified medium-grained sands. These sands were penetrated by the piece of oak wood. Both the OSL dating of the sandy deposits and the dating of the oak wood (C14 and dendrochronology) point to the 9th century A.D. when the Great Moravia Empire was on its peak expansion. Active fluvial channel was probably used as a part of the fortification system and a possible wood bridge existed here in the front of the proposed Western Gate of the Pohansko agglomeration. Palynological studies reveal some fragmentation of the landscape and agricultural activities in the close surroundings. Deposits of the studied fluvial channel were covered by the beds of the younger flood loams.
Speech behaviour of Internet users in conflict communication
Authors: Tillabaeva A. A. , Shulginov V. A.
Published: November 2020

This article explores the expression of impoliteness of Internet users in confrontational threads. This approach involves the identification of speech aggression markers typical of a certain type of discourse. This makes it possible to define the roles and attitudes of partici­pants in the conflict interaction. The authors employed methods of discourse analysis and corpus tools of data collection and marking. Seven confrontational threads in the communities of the social network "Vkontakte" were analysed. The authors identified language markers of the switch from cooperative to confrontational speech interaction. The authors investigated the typical roles of communicators in a confrontational thread, and observed the dynamics of using aggressive language tools for each of the proposed strategies. The article describes typi­cal situations for the confrontational threads: reliability of the information presented, lack of the user's intention to check facts, and the violation of spelling and punctuation rules. Con­frontations around these situations tend to lead to more complex conflicts and are character­ized as motives typical of impolite communication.
Acute high-altitude illness: updated principles ofpathophysiology, prevention, and treatment
Authors: Berger MM , Schiefer LM , Treff G , Sareban M , Swenson ER , Bärtsch P
Published: November 2020

The interest in trekking and mountaineering is increasing, and growing numbers of individuals are travelling to high altitude. Following ascent to high altitude, individuals are at risk of developing one of the three forms of acute high-altitude illness: acute mountain sickness (AMS), high-altitude cerebral edema (HACE), and high-altitude pulmonary edema (HAPE). The cardinal symptom of AMS is headache that occurs with an increase in altitude. Additional symptoms are anorexia, nausea, vomiting, dizziness, and fatigue. HACE is characterized by truncal ataxia and decreased consciousness that generally but not always are preceded by worsening AMS. The typical features of HAPE are a loss of stamina, dyspnea, and dry cough on exertion, followed by dyspnea at rest, rales, cyanosis, cough, and pink, frothy sputum. These diseases can develop at any time from several hours to 5 days following ascent to altitudes above 2,500-3,000 m. Whereas AMS is usually self-limited, HACE and HAPE represent life-threatening emergencies that require timely intervention. For each disease, we review the clinical features, epidemiology and the current understanding of their pathophysiology. We then review the primary pharmacological and non-pharmacological approaches to the management of each form of acute altitude illness and provide practical recommendations for both prevention and treatment. The essential principles for advising travellers prior to high-altitude exposure are summarized. Key Words: Acute Mountain Sickness, High Altitude Cerebral Edema, High Altitude Pulmonary Edema, Hypoxia
Dos Jogos Olímpicos da Antiguidade às olimpíadas de matemática: a constituição de atletas
Authors: Silva Patrícia Lima da , Duarte Claudia Glavam
Published: November 2020

Este artigo emerge de um estranhamento causado ao observar as olimpíadas de matemática se naturalizando nas escolas brasileiras e os estudantes sendo qualificados como atletas da matemática. Impulsionadas por tal estranhamento desenvolvemos uma digressão histórica remontando à Grécia Antiga durante o período de desenvolvimento dos Jogos Olímpicos da Antiguidade, onde destacamos o momento pitagórico e o momento platônico por darem visibilidade tanto às competições atléticas quanto à matemática. Nesse movimento usamos conceitos da filosofia da diferença para construirmos nosso caminho. Em particular, trabalhamos com o conceito de gagueira de Deleuze para variar o conceito de história de Foucault. Com as análises efetuadas sobre os Jogos Olímpicos da Antiguidade, o momento pitagórico e o momento platônico pontuamos continuidades e descontinuidades entre essas práticas e as olimpíadas de matemática da contemporaneidade. Inferimos que a constituição de atletas pode se configurar no eixo que aproxima tais práticas.
APRENDER matemáticaS: UM ENCONTRO COM SIGNOS
Authors: Da Silva Michela Tuchapesk , Tamayo Carolina
Published: November 2020

Este texto tem por objetivo mobilizar a teoria do signo de Gilles Deleuze, junto a algumas ações práticas e teóricas realizadas com os(as) alunos(as) das disciplinas de estágio supervisionado de duas Licenciaturas em Matemática. Por meio de uma escrita (im)pertinente, descompactada e que dança num ritmo descontraído com a vida que acontece na escola, buscamos tensionar, desnaturalizar e provocar outras formas de compreender o aprender matemáticaS, vinculado ao pensar como ação e não como resultado da recognição. Encontramos na proposta deleuziana, tecida com as (im)pertinências produzidas pelos professores em formação inicial, a possibilidade de pensar um aprender com signos, um aprender pelos afectos, em que se manifesta um pensar que nasce e renasce para liberar a afirmação da diferença.
The Multi-Etnik Community Integration Model in Bali: Pholosphical Base and Proto Multiculturalism in Balinese Society
Authors: Suastika I Nengah , Sudika Mangku Dewa Gede , Rai Yuliartini Ni Putu , Lasmawan I Wayan
Published: November 2020

Ethnic conflicts that occurred in various regions in Indonesia did not occur in Bali Province. There is a set of values that are used as the basis for building unity in diversity. These values are crossed and cut, so they can be used as shared values and unifying values. This research aims at describing the integration of multicultural society’s shared place of worship and the integration of multicultural society in traditional organizations in Bali Province. This study used a qualitative approach, which described the integration model of Balinese multicultural society based on etic and emic perspectives. The research instruments used were interview guidelines, observation guidelines, and documentation study guidelines. The integration model of multicultural communities in Bali is developed on religious activities through the construction of a shared place of worship in one area, with temples and musholla. In the social life, A multi-ethnic community established common traditional organizations such as Pecalang and Subak which protect all people. The establishment of multicultural society integration in Bali is due to the shared values that are believed by the multi-ethnic community and the existence of traditional cross-cutting organizations. The shared values are used as guidelines for living together in religious, social and cultural activities.
A note on attractivity for the intersection of two discontinuity manifolds
Authors: Difonzo Fabio V.
Published: November 2020

In piecewise smooth dynamical systems, a co-dimension 2 discontinuity manifold can be attractive either through partial sliding or by spiraling. In this work we prove that both attractivity regimes can be analyzed by means of the moments solution, a spiraling bifurcation parameter and a novel attractivity parameter, which changes sign when attractivity switches from sliding to spiraling attractivity or vice-versa. We also study what happens at what we call attractivity transition points, showing that the spiraling bifurcation parameter is always zero at those points.
Existence and decay of finite energy solutions for semilinear dissipative wave equations in time-dependent domains
Authors: Nakao Mitsuhiro
Published: November 2020

We consider the initial-boundary value problem for semilinear dissipative wave equations in noncylindrical domain \(\bigcup_{0\leq t \lt\infty} \Omega(t)\times\{t\} \subset \mathbb{R}^N\times \mathbb{R}\). We are interested in finite energy solution. We derive an exponential decay of the energy in the case \(\Omega(t)\) is bounded in \(\mathbb{R}^N\) and the estimate \[\int\limits_0^{\infty} E(t)dt \leq C(E(0),\|u(0)\|)< \infty\] in the case \(\Omega(t)\) is unbounded. Existence and uniqueness of finite energy solution are also proved.
ANALYSIS OF THE FOCUSING EFFECTS OF CONDUCTING FOILS ON THE RELATIVISTIC ANNULAR BEAMS AND FIRST EXPERIMENT RESULTS OF THE EFFECTS OF THE FOILS ON BEAM BUNCHING
Authors: WANG PING-SHAN  , HUANG HUA  , CHEN TIAN-CAI  , XIA LIAN-SHENG  , TAO ZU-CONG  ,   (1)成都应用电子学研究所,成都610003; (2)中国工程物理研究院,成都610003
Published: November 2020

The focusing ability of the image charges on annular beams is analyzed, and the image charge is on the conducting foils which are placed perpendicular to the beam axis. The given calculating results can be employed to select the geometrical parameters of the foils for annular beam focusing. The first image charge focusing relativistic klystron amplifier experiment was done to study the effects of the foils on the bunching process. Although the transparancy of the foils to the beam is only 0.88, the results show that the foils do not affect the beam bunching process.
USING NONLINEAR DELAYED FEEDBACK ON POINCARE SECTION TO CONTROL CHAOS
Authors: YANG SHI-PING  , TIAN GANG  , XU SHU-SHAN  , HU GANG  ,   (1)北京师范大学物理系,北京100875; (2)河北师范学院物理系,石家庄050091
Published: November 2020

A new method of the nonlinear delayed feedback on a Poincare section is used to stabilize the unstable periodic orbits (UPO) embedded in a chaotic attractor. As examples we studied the casee of Henon map and two-photon laser system with an injected signal. The advantages of this method are that it does not need to know the linear properties and the periodicity about a UPO or the one of the UPO extracted from the chaotic attractor, and the convergence to UPO does not depend on time of appling delayed feedback control action.
PULSE-CURRENT LINEARLY POLARIZED WIGGLER WITH LOOPED WIRE
Authors: HU JIAN-PING  , HU KE-SONG  , CHEN YU-TAO  ,   西南应用电子学研究所,成都610003
Published: November 2020

In this paper, a new type of linearly polarized wiggler, its the magnetic field amplitude and peri-od of which can be varied conveniently, has been investigated in detail. The wiggler consists of many loops which separately arrange on the wiggler framework. Varying the radius and period, we can ob-tain the field profile as was expected. The theory about the magnetic field profile in the wiggler has been derived and results of computer simulation show that it can produce any magnetic field profile that we desire by following methods:a)variation of loop radius only;b)variation of the wiggler period only;c) variation of the both.
AN XPS STUDY OF Mn THIN FILMS GROWN ON GaAs(001l) SURFACE
Authors: XU MIN  , ZHU XING-GUO  , ZHANG MING  , DONG GUO-SHENG  , JIN XIAO-FENG  ,   (1)复旦大学李政道物理学综合实验室,应用表面物理国家重点实验室,上海200433; (2)浙江工业大学基础部,杭州310014
Published: November 2020

The composition depth profiles of the Mn thin films grown on GaAs(00l) surface using MBE technique are studied with X-ray photoelectron spectroscopy(XPS) . The experimental results show that the fcc-Mn/GaAs(001) system grown on a 400 K substrate has a sandwich structure with a Mn-Ga-As buffer layer located between the fcc-Mn layer and the GaAs substrate; the α-Mn/GaAs (001) system grown on a 300 K substrate also has a similar buffer layer which is much thinner than that of the fcc-Mn/GaAs(001) system;and the system grown on a 450 K substrate is a Mn-Ga-As alloy beyond the GaAs substrate and it has no Mn-dominated area. It is concluded that to keep the substrate at a proper temperature(400 K) during growth to obtain a suitable thickness of buffer layer is an essential requirement to grow fcc-Mn on GaAs(00l) surface.
A PHENOMENOGICAL THEORY FOR GIANT MAGNETO-RESISTANCE IN NON-DISSOLUBLE MAGNETIC GRANULAR ALLOYS
Authors: ZHAO PING-BO  , LI BO-ZANG  , PU FU-KE  ,   中国科学院物理研究所,北京100080
Published: November 2020

In virtue of stochastic autocorrelation function description of the impurity scattering potential in non-dissoluble magnetic-nonmagnetic granular films, we find a relationship between the resistivity of system and the size of gruanules. Furthermore, by introducing a phenomenological factor to account for the increase of correlation length caused by the external magnetic field, we get an analytical ex-pression for the giant magnetoresistance coffiecient. The calculations show that our theory agrees qualitatively with the experimental results.
HIERARCHICAL NETWORK WITH A WIDE DISTRIBUTION OF CONDUCTANCE
Authors: CHEN RU-HONG  , MA BEN-KUN  ,   (1)北京师范大学物理系,北京100875; (2)北京医科大学物理教研室,北京100083
Published: November 2020

Some scaling behaviors of a fractal resistor network are studied based on a hierarchical model with an exponentially wide distribution obeying g=g0eWx. We analyse the effects of the disorder width W on the overall resistance and the moments of distributions, and corresponding universal curves are found. We regard the problem as a crossover behavior between the competing effects of the size of the network and the width of the distribution of conductances. Our results are in good agreement with the numerical simulation reported by Tong on Sierpinski honeycomb network.
NEW PERFORMANCE OF RADIO FREQUENCY FAR INFRARED WAVEGUIDE FREE ELECTRON LASER
Authors: HU SU-XING  , FU EN-SHENG  , XU ZHI-ZHAN  ,   中国科学院上海光学精密机械研究所,上海201800
Published: November 2020

Idealizing the ultrashort pulse electron beam modulated by radio-frequency as a delta function on time scale, we calculate the coherent synchrotron radiation emitted by the electron micropulse in a rectangular waveguide with the method of eigenmode expansion. We find that when the frequency of radiation is the integral times of the radio frequency ωrf, the radiation field pattern will appear as "pure" eigenmodes of waveguide. In addition, we analyse the frequency performance of the coherent synchrotron radiation and the slippage effect. And finally, the gain of a rectangular electron pulse amplifying the radiation is deduced.
RELATION BETWEEN Tg AND α-PEAK IN AMORPHOUS POLYMER PVC
Authors: LI JIAN  , ZHANG YE  , ZHANG SHENG-CHUN  ,   (1)中国科学技术大学结构分析开放研究实验室,合肥230026; (2)中国科学院固体物理研究所内耗与固体缺陷开放研究实验室,合肥230031; (3)中山大学材料研究所,广州510275
Published: November 2020

A systematic study of the effect of physical ageing and cooling rate on a-relaxation peak are carried out in PVC. It was said that a-peak and Tg are not the same concept. Both are closely connected with amorphous state, but show different behaviours in the same pre-treatment conditions: varying physical ageing time in sub- Tg or changing cooling rate from Tg + 20℃ to room temperature . Some interesting results were obtained as follows:When Tg lowers with increacing ageing time or decreacing cooling rate, a-peak temperature (Tα) keeps constant. On the other hand, the intensity of the a-peak decreases. This behaviour shows that a- relaxation peak is not a typical linear anelastic internal friction peak, as there is a quenching peak added on it.A detail discussion will be given in this paper.
THE ETCH PITS OF DISLOCATIONS AND SYMMETRY GROUP IN Bi12GeO20 CRYSTAL
Authors: ZHANG XING-KUI  , LIU XIAN-JIE  , XU XIU-YING  , Lü PENG  ,   南京大学物理系、固体物理研究所,南京210008
Published: November 2020

The etch pits of dislocations in Bi12GeO20 crystal at (100), (110) and (111) planes have been studied by means of chemical etching. The pattern of etch pits are very special compared with the common cubic system crystal, and we have analyzed it with theory of symmetry group. The patterns of etch pits by theoretical analysis are in conformity with the experiment. It shows that the pettern of etch pits of dislocations consists of {112} planes. It is clear that the habitual plane of crystal of Bi12GeO20 crystal is {112} plane.
KINETICS OF ORDERING AND 2-DIMENSIONAL GROWTH OF Ag ON Si(111)
Authors: LI MING  , XU MING  , LIU HUI-ZHOU  ,   中山大学物理系,广州510275
Published: November 2020

We have studied the ordering processes of Ag on Si (111) by LEED using a homemade high re-solution spot profile measuring equipment. The results show that the growth processes of Ag 31/2 domain satisfy scaling symmetry. They are self-similar growth processes. The studies also show that the growth exponent is near 1/2 in the early stage of the growth processes. We propose a growth mechanism of Ag diffusing from Ag(111) islands to form Ag 31/2 domains. This article also suggests a way to obtain perfect surface structures in lower temperature by using light-assisted anneal.
RAMAN SCATTERING STUDY AT HIGH TEMPERATURE ON BaTiO3 and Ce:BaTiO3 SINGLE CRYSTALS
Authors: JIANG YI-JIAN  , ZENG LING-ZHI  , WANG RONG-PING  , ZHU YONG  , LIU YU-LONG  ,   (1)北京工业大学应用物理系,北京100022; (2)中国科学院物理研究所,北京100080
Published: November 2020

Raman spectra of BaTiO3 and Ce: BaTiO3 single crystals have been recorded between room temperature and 180℃. Three new bands at 986,1204 and 1480 cm-1 in the X(ZZ) Y geometry are discovered. Based upon the temperature dependence of Raman scattering cross sections, the new bands are attributed to the second-order Raman spectra of BaTiO3, while the strong asymmetry bands at 275 and 514 cm-1 in A1(TO) spectrum are confirmed to be of first order. On the basis of above results, the Raman spectra of cubic BaTiO3 and the model of phase transitions are discussed. It is found that doping with Ce in BaTiO3 lowers its Curie temperature, which agrees with the experimental results of dielectric constants.
ELECTRON TRANSITION PROCESS OF MyM′1-yFClxBr1-x:Sm2+ AND SPECTRAL HOLE-BURNING EFFICIENCY
Authors: SONG HONG-WEI  , ZHANG JIA-HUA  , ZHAO YU  , HUANG SHI-HUA  , YU JIA-QI  ,   中国科学院长春物理研究所激发态物理开放研究实验室
Published: November 2020

By measuring the excitation spectra of the 4f5d bands and the fluorescent decays of the 5ＤJ—7Ｆ0（Ｊ＝２，１，０） transition probability depending on temperature in MyM′1-yFClxBr1-x:Sm2+(M=Mg,Ca,Sr,Ba)series, we have studied the dependence of the energy separation between the 4f5d bands and the 5ＤJ level, the 5ＤJ—7Ｆ0（Ｊ＝２，１，０） transition probability on the composition grade(x) and (y) and the effect on hole-burning efficiency. We draw conclusions as below: In MyM′1-yFClxBr1-x:Sm2+ series, the 4f5d bands will be more close to the 5ＤJ level with the increase of the Br concentration and the concentration if snakk radium alkaline earth ion, and this situation makes the 5ＤJ—7Ｆ0 electron transition probability increase. By reasoning, the hole-burning efficiency of Sm2+ are expected to by enhanced.
HIGH-ORDER RELATIVISTIC GENERATION BY INTENSE LASER PULSE
Authors: ZENG GUI-HUA  , YU WEI  , SHEN BAI-FEI  , XU ZHI-ZHAN  ,   中国科学院上海光学精密机械研究所
Published: November 2020

The characteristics of high-order relativistic harmonic generation excited by intense laser pluse in underdense plamas is inverstigated. With quasistatic approximation, the growth and saturation of Nth-order relativistic harmonics are analyzed, and the ratio of high-order power to fundamental wave power is described and calculated.
STUDY ON FRACTAL STRUCTURE OF POROUS SILICA:AEROGELS AND XEROGELS
Authors: SHEN JUN  , WANG JUE  , WU XIANG  ,   同济大学波耳固体物理研究所
Published: November 2020

Porous materials silica aerogels and xerogels were obtained through a sol-gel process from TEOS. Samples derived from different preparation circumstances were investigated via small-angle X-ray scattering. The power-law dependence of the scattered intensity, a characteristic of fractal structures, was observed for all the one-step aerogels. While for the xerogels and aerogels derived from a two-step sol-gel process, the power-law dependence of the scattered intensity was not observed. The xerogels are found to consist of a number of large spherical particles which were densely packed together.
GROWTH CHARACTERISTICS OF Bi2Sr2CaCu2Oy SINGLE CRYSTALS USING SELF-FLUX
Authors: XU ZHENG  , ZHAO XIAO-RU  , WU WEN-BIN  , SUN XUE-FENG  , ZHOU GUI-EN  , LI XIAO-GUANG  , ZHANG YU-HENG  ,   (1)同济大学材料科学与工程系;中国科学技术大学结构分析开放研究实验室; (2)中国科学技术大学结构分析开放研究实验室
Published: November 2020

Growth characteristics of Bi-2212 single crystals using self-flux Bi2O3 have been experimentally studied systematically. Some of the problems encountered in the growth of crystals in the Bi system, such as the amounts of flux, thermal cycle, contamination of the crucible materials, melting incongruency, remarkable anisotropic growth rate and intergrowth of Bi-2201 phase, are discussed in detail.
A NEW METHOD TO ACHIEVE THE BLUE/GREEN LIGHT-EMITTING FROM POROUS SILICON
Authors: LI GU-BO  , ZHANG FU-LONG  , FAN HONG-LEI  , CHEN HUA-JIE  , YU MING-REN  , HOU XIAO-YUAN  ,   (1)复旦大学应用表面物理国家重点实验室; (2)四川工业学院物理实验室
Published: November 2020

After the treatment of porous Si by "amine immersion and rapid thermal oxidation", the peak position of the photoluminescence spectra has a blue shift to 500nm. Only a little change in photoluminescence was observed after 160d storing in dry air. FTIR spectra indicate that the compositions of such treated sample are mainly silicon and oxygen. ESR signal shows that the blue/green light-emitting sample has rather low density of dangling bonds. These results demonstrete that the quantum confinement effect and surface states play a key role in blue/green light emitting. This method is simple and practicable, to make blue/green light-emitting samples and its success ratio can achieve 70%.
PHOTOLUMINESCENCE OF SPONTANEOUSLY ORDERED Ga0.5In0.5P ALLOY UNDER HYDROSTATIC PRESSURE
Authors: LI GUO-HUA  , LIU ZHEN-XIAN  , HAN HE-XIANG  , WANG ZHAO-PING  , DONG JIAN-RONG  , LU DA-CHENG  , SUN DIAN-ZHAO  , WANG ZHAN-GUO  ,   (1)中国科学院半导体研究所; (2)中国科学院半导体研究所半导体超晶格国家重点实验室
Published: November 2020

The photoluminescence of spontaneously ordered Ga0.5In0.5P alloy has been measured at room temperature and under hydrostatic pressure up to 7GPa. The direct-band gap of three ordered samples is lower than that of disordered sample by 115,92 and 43 meV at normal pressure, respectively. Their pressure coefficients are also reduced from 92meV/GPa of the disordered sample to 75,81 and 83meV/GPa for three ordered samples. Both the narrowing of the band gap and the reducing of its pressure coefficients can be well explained using a Γ-Ｌ interaction model. The obtained Γ-Ｌ interaction poteraction potential is 0.19,0.15 and 0.10 eV for three ordered samples, respectively. It confirms that the [111] order in the spontaneously ordered Ga0.5In0.5P alloy is the main reason for the band-gap narrowing. An obvious Γ-X anticrossing has been observed in sample C,but the Γ-X interaction potential(0.011eV)is one order of magnitude less than the Γ-L interaction. It indicates that a weak [001] order coexists with the main [111] order in sample C.
EXACT SOLUTION OF THE FWM IN PLASMAS IN THE CASE OF REFLECTION GRATING
Authors: MENG YUE-DONG  ,   中国科学院等离子体物理研究所,合肥230031
Published: November 2020

The universal degenerate and nearly degenerate FWM nonlinear equations in uniform magnetized plasma are given for the formation of reflection grating configuration and its exact solution appropriated for arbitrary complex coupling parameters under undepleted pump assumption is obtained. The solution is quite suited to various plasma situations but also can be extended to photorafractive materials. It is hoped that it may be helpful for further studying FWM' s phase conjugation theory and developing new nonlinear optical device , especially , for developing new fusion diagnostics by using FWM's principle.
BAND STRUCTURAL PROPERTIES OF β-C3N4, β-Si3N4 AND β-Ge3N4
Authors: DUAN YU-HUA  , ZHANG KAI-MING  , XIE XI-DE  ,   复旦大学物理学系,上海200433
Published: November 2020

The electronic energy bands of a series of β phases of carbon nitride, silicon nitride and germanium nitride have been calculated using a first-principle linear combination of muffin-tin orbital method with the atomic-sphere approximation(LMTO-ASA). The band gaps obtained for the three compounds are 4. 1751,5. 1788 and 4. 0279 eV, respectively. For β-C3N4 ,the nitrogen 2p orbitals plays an important role in the top of valence band(VB) due to its non-bonding. For -β-Si3N4,the silicon 3d orbitals plays an important role both in the VB and in the conduction band(CB). Its band gap is indirect which is in agreement with other calculated results. For β-Ge3N4,the germanium 3d orbitals preserve the characteristics of atomic orbitals and give very little contributions to other VBs and CB. Its 4d empty orbitals play a role analogue to 3d of Si of β-Si3N4. This is the frist theoretical study reported on the electronic structure of β-Ge3N4.
INFLUENCE OF CAVITY LOSS ON GENERATION OF STEADY STATE FOURTH-ORDER AND SQUARED AMPLITUDE SQUEEZING IN MICROMASER
Authors: LI FU-LI  ,   西安交通大学应用物理系,西安710049
Published: November 2020

The generation of the steady state fourth-order squeezing and squared amplitude squeezing in a micromaser by the coherent trapping approach is investigated. The results show that if two-level atoms injected into the cavity are initially in coherent state and the flight time of the atoms inside the cavity satisfies the trapping condition, the field can evolve into a coherent trapping state which exhibits steady state fourth-order squeezing and squared amplitude squeezing in the cavity as long as the flux of the atoms is moderately large.
ANALYSIS OF EFFECTIVE TIME OF INTERACTION BETWEEN ELECTRON AND RADIATIVE WAVE IN THE FEL
Authors: ZHAO DONG-HUAN  ,   中国科学院上海光学精密机械研究所,上海201800
Published: November 2020

The expression of uniform grow rate of laser is derived by using the high - signal gain formula of FEL, the effective time of interaction between electron and radiative wave in the FEL is analysed, and the effects of major physical parameters on the effective time of interaction are discussed.
THE HELICAL INSTABILITY OF ARCS FOR LINEAR HEAT FLUX POTENTIAL MODEL IN AN AXIAL MAGNETIC FIELD
Authors: LIU JIN-YUAN  , GONG YE  , LI GUO-BING  , MA TENG-CAI  , ZHANG LIN  ,   大连理工大学三束材料改性国家重点实验室,大连116023
Published: November 2020

The helical instability of an arc column with electrical conductivity of the distribution of the linear heat flux potential (a new "temperature") is discussed in axial magnetic field. The magnetohy-drodynamic equations serve as the starting point of the theory. In an electrostatic approximation and a linear time dependent perturbation theory, the perturbation equations for the arc column movement are deduced. Solutions of these equations are obtained analytically, from which the stability limit of the cylindrical arc and the growth rate of the helical instability are given. In comparison the results with those of uniform current distribution, it is found that the stable area is enlarged.
STUDY ON UP-CONVERSION LUMINESCENCE RESEARCH OF TmP5O14 CRYSTAL
Authors: CHEN XIAO-BO  , ZHANG GUANG-YIN  , FENG YAN  , LIU YAN-BIN  , LI JIA-JI  , SONG ZENG-FU  ,   (1)北京大学物理系,北京100871; (2)北京人工晶体研究所,北京100018; (3)南开大学物理系,天津300071
Published: November 2020

The up-conversion luminescence phenomenon of TmP5O14 crystal at room temperature pumped by pulsed DCM dye laser is studied. It is found that there appear strong 450 and 360 nm and weak 347 nm fluorescences. Through careful experiment al investigation and theoritical analysis, we find that the 450 and 360 nm radiations are 1D2→3F4,3H6 two-photon upconversion fluorescence and 347 nm radiation is 1I6→3F4 three-photon fluorescence. The up-conversion process can be elucidated as follows: when a Tm3+ ion absorbs a first pumping photon and reaches the 3F2 state from the 3H6 bound state, the population of 3F2 state falls down rapidly to the 3H4, state due to the rather strong nonradiative relaxation. Then the excited state absorption from 3H4 to 1D2 takes place and the 360 nm two-photon up-conversion fluorescence from 1D2 state is appears. Meanwhile, there is a small possibility for energy transfer between 1D2 state and 3H4 state. It results in a converted population with respect to the 1I6 state and the 347 nm three-photon up-conversion fluorescence is appear, the up-con-version mechanism of which is a complicated process involving both the excited state absorption and the temperature of photons.
DOUBLE WAVE DESCRIPTION OF THE MOTION FOR A CHARGED PARTICLE IN MASS SPECTROMETER
Authors: HUANG XIANG-YOU  ,   北京大学物理系,北京100871
Published: November 2020

When and where a charged particle with given energy will enter or leave the magnetic field in a mass spectrometer, and how we use quantum mechanics to calculate them are interesting problems. The double-wave description of the system leads to the results that are similar to that of classical mechanics but the energies of particles take quantized discrete values.
HIGH-POWER, INTENSE-CURRENT-DENSITY, LOW-EMITTANCE, HIGH-BRIGHTNESS PSEUDOSPARK ELECTRON BEAM DRIVEN BY IMPROVED PULSE LINE ACCELERATOR
Authors: ZHU JUN-BIAO  , WANG ZHI-JIANG  , ZHANG LI-FENG  , LU ZAI-TUN  , HUANG YU  , WANG MING-CHANG  ,   (1)中国科学院上海光学精密机械研究所,上海201800; (2)中国科学院上海光学精密机械研究所,上海201800;中国科学院高能物理研究所应用部,北京100080
Published: November 2020

High-power ( 200 kV), intense-current-density, low-emittance, high-brightness electron beam was generated in a 10 gap pseudospark chamber filled with 15 Pa N2 and driven by an improved pulse line accelerator. The ejected electron beam was characterized by 1mm diameter, 2. 2 kA beam current, and 400ns pulse length, and propagated 20cm in neutral N2 ionizing channel in the drift tube. At 5 cm downstream of the anode, it penetrated consecutively an acid-sensitive discoloring film and a 0.05 mm-thick copper foil, and left 0.6 mm and 0.3 mm holes on them, separately. According to the pinching equilibrium condition, the beam's normalized emittance and brightness are respectively calculated to be 23 πmm-mrad and 8×1010A/(m rad)2. That the 10 shots on the same acid-sensitive film produced a hole of 1. 6mm in diameter at 7cm showed a good repeatability of the electron beam. After 60 shots the pseudospark chamber was observed that there was almost no destructive damage traces left on the surfaces of the electrodes and insulators. It was found that the quality of electron beam produced in the pseudospark discharge chamber driven by the modified pulse line accelerator is much better than that generated by cold cathode discharges.
HIGHER-ORDER SQUEEZING OF ATOMIC DIPOLE
Authors: DONG CHUAN-HUA  ,   上海大学基础部,上海200072
Published: November 2020

The higher-order fundamental quantum-mechanical fluctuation is given on the base of the higher-order uncertainty relation, from which the definition of higher-order squeezing for atomic dipole is introduced. As an example, we examine the second-, fourth-and sixth-order squeezing of atomic dipole in the two-photon Jaynes-Cummings model with the two-photon superposition state preparation.
TEMPORARY RESPONSE OF PHASE CONJUGATION WAVE AND GRATING PROPERTIES IN BR-PVA FILM IN DFWM FIELD
Authors: TANG GUO-QING  , YUE ZHENG-SHAN  , ZHANG GUI-LAN  , CHEN WEN-JU  ,   南开大学现代光学研究所,天津300071
Published: November 2020

In this paper the theoretical and experimental studies on the properties of phase conjugate (PC) wave and the gratings formed as a result of degenerate four-wave mixing (DFWM) interference field of Ar+ laser in bacteriorhodopsin-polyvinyl alcohol (BR-PVA) solid film are reported. The diffraction efficiency temporary response and saturation property of the PC wave are described by useing a simplified double state model and the method of rate equation combined with a diffraction theory of holograph grating. The mechanism of forming grating in the film and the dependence of the properties mentioned above on polarization states, intensities are analysed. The time of arriving at the sample of three input beams and initial concentration of grating formed in the film are discussed. The theoretical results are in good agreement with the experimental observations.
ELECTROLUMINESCENCE FROM NANOSCALE Si-PARTICLES EMBEDDED SiO2 FILMS DEPOSITED ON n+-Si AND p-Si SUBSTRATES
Authors: ZHANG YA-XIONG  , LI AN-PING  , CHEN KAI-MAO  , ZHANG BO-RUI  , SUN YUN-XI  , QIN GUO-GANG  , MA ZHEN-CHANG  , ZONG WAN-HUA  ,   (1)北京大学物理系; (2)电子工业部第13研究所
Published: November 2020

The structures of Au/Si-rich SiO2/p-Si and Au/Si-rich SiO2/n+-Si have been fabricated and their electroluminescence characteristics have comparatively been studied. For the Au/Si-rich SiO2/p-Si structure, when the forward bias is more than 4V, red light is emitted, while under the reverse bias, no light is observed. For Au/Si-rich SiO2/n+-Si structure, it does not emit light under the forward bias, but it emits red light when the reverse bias is greater than 3.5V. The mechanism for electroluminescence from the Au/Si-rich SiO2/n+-Si structure is disscussed.
THE STUDY OF ENERGY RESOLUTION FOR SOFT X-RAY MULTILAYER MONOCHROMATER
Authors: CUI MING-QI  , MIAO JIAN-WEI  , WANG JUN  , CUI CHONG-WU  , LI GANG  , ZHU PEI-PING  ,   (1)Physics Department,State University of New York at Stony Brook,Stony Brook,New York 11794-3800,USA; (2)中国科学院高能物理研究所
Published: November 2020

A theoretical method to obtain the soft X-ray multilayer monochromater of-better energy resolution is put forward. The basic point is to choose the alternating elements with new criterions instead of general choosing method of high-and low z elements. Moreover, a simple and practicable multilayer designing method to achieve high reflectivity was presented. The some results of soft X-ray multilayer monochromater study in recent years on Beijing Synchrotron Radiation Facility (BSRF) have been given out.