P systems with array objects and array rewriting rules

Array P systems were introduced by Paun Gh. which is linking the two areas of membrane computing and picture grammars. Puzzle grammars were introduced by us for generating connected picture arrays in the two-dimensional plane, motivated by the problem of tiling the plane. On the other hand, incorporating into arrays the developmental type of generation used in the well-known biologically motivated L systems, Siromoney and Siromoney proposed a very general rectangular array generating model, called extended controlled tabled L array system (ECTLAS). In this paper we introduce two variations of the array P system, called BPG array P system and parallel array P system. The former has in the regions array objects and basic puzzle grammar rules (BPG), which are a specific kind of puzzle grammar rules. In the latter, the regions have rectangular array objects and tables of context-free rules. We examine these two types of P systems for their array generative power.     

Phylogenetic relationships of native and introduced Bemisia tabaci (Homoptera:Aleyrodidae) from China and India based on mtCOI DNA sequencing and host plant comparisons

Phylogenetic relationships for Bemisia tabaci were reconstructed by analysis of a ～780 bp fragment of the mitochondrial cytochrome oxidase I (mtCOI) gene with an emphasis on geographic range and distribution among eight eudicot plant families that are common hosts of B. tabaci worldwide to elucidate key phylogeographic linkages between populations extant in China (n=31) and India (n=34). Bootstrap values for the Maximum Parsimony tree were highly robust for all major nodes involving the major Asian clade, subgroups, and sister groups within, at 92%—100%. Between-clade distances for the Southeast Asia and three other major clades, e.g. from sub-Sahara Africa, North Africa-Mediterranean, and the Americas, were approximately >16% divergent. Two major Asian subgroups (I, II) were resolved, which represented populations indigenous to the region, comprising two (I a, I b) and five (II a—e) sister groups, respectively, which diverged by 11%. Two distinct populations from sunflower in Hyderabad grouped separately within the two Asian subgroups. All other populations grouped uniquely within Asian subgroup II or I. The “B” biotype was identified in 23 collections from China at 97.3%—99.5% nucleotide identity with “B” biotype reference sequences; it was not identified in collections from India. The majority of haplotypes were associated with 3—4 plant families, with one exception that for sister group IId (sesame, India), it might be monophagous. Thus, B. tabaci from the southeastern and near eastern regions of the Asian continent comprise of a large number of ancestral, richly divergent, mostly polyphagous populations. This region is therefore hypothesized to constitute an important Old World center of diversification for the B. tabaci complex, together with sub-Saharan Africa.     

色散耦合道光学模型对28Si的核子散射数据分析

在光学势中引入色散关系, 相比于通常的耦合道光学模型, 极大地减少了光学势 参数的个数. 采用基于软旋转子模型的耦合道方法对较轻形变核²⁸Si核的中子和质子散射实验数据进行了计算分析, 拟合得到一组色散光学势参数. 计算的中子总截面、以及中子、质子的弹性与非弹性散射微分截面与实验数据有较好的符合.     

低能离子束横向发射度的测量及分析

The transverse emittance of an ion beam describes its transverse size as the particles are transported from a source to a target.It allows for predicting beam losses in limiting apertures and the beam focus size at the target.Various definitions and issues are discussed.The most common and emerging measuring techniques are presented,including their advantages.Several methods of emittance data analysis,their accuracy and trustworthiness,are discussed.     

CERN的ISOLDE装置上的ECR离子剥离器Phoenix的最新进展

At ISOLDE (CERN),an on-line test bench is dedicated to charge breeding experiments with a 14GHz Phoenix ion source,for the investigation of the 1 →n scenario at next generation ISOL-type facilities.This year,various technical developments have been undertaken for intensifying the tests of the on- line performances of the booster with a high diversity of stable and radioactive ion beams.This contribution will present an overview of the latest developments,the current challenges,and some perspectives for the future use of the Phoenix booster for physics experiments at ISOLDE.     

为IBA C70回旋加速器设计研制的采用Cusp场型H-离子源与产生He束的ECR离子源的双束轴向注入系统

At the moment,a 70MeV cyclotron is under construction by the IBA company.This cyclotron will be able to accelerate H~- beam from a multicusp source and with a beam intensity in the range of 10mA at the source extraction.A He~(1 2 ) beam is also required.This beam will be produced by a PANTECHNIK ECR ion source(SUPERNANOGAN)with an extracted current of 1 to 2mA.In this paper the studies and design of the two sources with a common axial injection in the cyclotron are described.     

NSCL溅射金属离子产生研究进展(摘要)

Production of metallic ion beams in support of the experimental program at the Coupled Cyclotron Facility at the NSCL required the development of ion sputtering feed of metallic molybdenum,nickel,uranium, and zirconium for use with the ARTEMIS ion source.The production of high intensity lower to medium charge state ions required high material consumption,posing some significant difficulties in reliable long term beam stability.Resultant and ongoing hardware and technique developments to resolve these difficulties will be presented in this poster along with interesting effects of the ion source solenoid field polarity on the sputtering process.     

邮票上的科学家——佼佼者之路

谨以此文奉献给有集邮爱好的科学工作者青少年朋友以及他们的教师和家长让我们:寓知识学习于休闲娱乐之中寓情趣陶冶于艺术欣赏之中寓耐性培养于日积月累之中寓风格塑造于潜移默化之中寓传统精神于历史沿革之中祝青少年朋友成为所在行业的佼佼者前言我在北京的碧云寺、武汉的归元寺、杭州的净慈寺和成都的宝光寺都见到了一种“神仙”聚会的地方——“罗汉堂”,数百位雕塑得栩栩如生、形态各异的罗汉“欢聚”一堂,让参观者仿佛置身于众神仙的保佑之中,从而得到了安全感、满足感和幸福感。在古代,由于生产力低下,人类同自然灾害搏斗的能力较低,因而产生了对菩萨、     

用于ECR离子源的超导磁体——设计与制造

Superconducting magnets are widely used in ECR ion sources.The intensity and form of the magnetic field plays an important role in the way towards higher performance sources.During the development steps,the design principles and geometries had to be adapted to reach higher fields using state-of-the-art technologies and design tools.Production,assembly,and tests of these superconducting magnets are presented and a short outlook on possible future developments is given.     

高频ECR离子源的最新进展

As they are first optimized for their ion losses,ECRISs are always under a fundamental compromise: having high losses and strong confinement at the same time.To help ECR ion source developers in the design or improvement of existing machines,general comments are presented in a review article being soon published. In this 160 pages contribution,fundamental aspects of ECRISs are presented,with a discussion of electron temperature and confinement and ion confinement.Then,as microwaves play a key role in these machines, a chapter presents major guidelines for microwave launching and coupling to ECR plasma.Moreover,once ECR plasma is created,understanding this plasma is important in ion sourcery;and a section is dedicated to plasma diagnostics with an emphasis on the determination of electron and ion density and temperature by vacuum ultraviolet(VUV)spectroscopy.Another chapter deals with the role of magnetic confinement and presents updated scaling laws.Next chapter presents different types of ECRISs designed according to the main parameters previously described.Finally,some industrial applications of ECRISs and ECR plasmas in general are presented like ion implantation and photon lithography.Some hints taken from this review article are presented in the following article.