Dielectric properties and phase transitions of La_2O_3- and Sb_2O_3-doped barium strontium titanate ceramics

The dielectric properties and phase transition characteristics of La2O3- and Sb2O3-doped barium strontium titanate ceramics prepared by solid state route were investigated. The microstructure was identified by X-ray diffraction method and scanning electron microscope was also employed to observe the surface morphologies. It is found that （La,Sb）-codoped barium strontium titanate ceramics exhibit typical perovskite structure and the average grain size decreases dramatically with increasing the content of Sb2O3. Both La3＋ ions and Sb3＋ ions occupy the A-sites in perovskite lattice. The dielectric constant and dielectric loss of barium strontium titanate based ceramics are obviously influenced by La2O3 as well as Sb2O3 addition content. The tetragonal-cubic phase transition of La2O3 modified barium strontium titanate ceramics is of second order and the Curie temperature shifts to lower value with increasing the La2O3 doping content. The phase transition of （La,Sb）-codoped barium strontium titanate ceramics diffuses and the deviation from Curie-Weiss law becomes more obvious with the increase in Sb2O3 concentration. The temperature corresponding to the dielectric constant maximum of （La,Sb）-codoped barium strontium titanate ceramics decreases with increasing the Sb2O3 content, which is attributed to the replacement of host ions by the Sb3＋ ions.

Magnetic and microwave absorbing properties of M-type barium ferrite/graphene oxide composite microwave absorber

In order to improve the absorbing properties of M- type barium ferrite absorbing materials, M-type barium ferrite/graphene oxide composites with different graphene oxide contents were synthesized by the sol-gel autocombustion method. X-ray diffraction （XRD）, a scanning electronic microscopy （ SEM ）, a physical properties measurement system （PPMS-9）, and a vector network analyzer were used to analyze their structure, surface morphology, magnetic and absorbing properties, respectively. The results show that the absorbing band of the composite absorbing material is widened and the absorbing strength is increased compared with the pure M-type barium ferrite. The sample with the content of doped graphene oxide of 3% has the minimum reflectivity at 10 to 18 GHz frequencies. Hence, the doped graphene oxide effectively improves the absorbing properties of M-type barium ferrite.

乡村振兴战略下农村群众体育赛事的多维价值、制约因素与铺展路径——基于“村BA热”的思考

农村群众性体育赛事高度契合人民群众对美好生活追求的时代需要,是助力乡村振兴战略的重要抓手。采用文献资料法、逻辑分析法等研究方法,基于“价值探析—因素审视—路径铺展”的整体逻辑框架,旨在诠释乡村振兴战略背景下我国农村群众体育赛事的多重功能与作用,探明当前制约农村群众体育赛事进一步发展的潜在影响因素,并提出解决思路。研究认为:从实践成效来看,农村群众体育赛事具备产生经济效益、放大社会效益、提高社区凝聚力、促进社会发展以及改善农民生活等功能,为乡村产业兴旺、生态宜居、乡风文明、有效治理及生活富裕提供了助力支点。从理论与实践视角出发,发现乡村生活挖掘不充分、专业人才储备不充裕、乡村文化建设不到位、生态特色功能不明显、社会组织力量不聚合等是制约我国农村群众体育赛事进一步高质量发展的潜在制约因素。因此,提出坚持讲述乡村美好生活,深化赛事本质内涵;强化乡村人才效应,保障赛事运作质量;优化乡风文明环境,提升赛事开展活力;凸显乡村生态特色,扩大赛事承办优势;发挥乡村组织合力,增强赛事治理效能等铺展路径。

New method for measuring high field electrostrictive response of barium titanate/polyurethane elastomer

A new method for measuring the characteristic of electrostriction by a digital speckle correlation method （DSCM） is presented. The in-plane displacement is obtained by using the DSCM, and the out-plane displacement is obtained by the geometrical relation of the triangle theory. In this application, high field electrostrictive strains of barium titanate/polyurethane elastomer composite materials are measured. The electrostrictive strain is evaluated when the application of an electric field is repeated, and then the electrostrictive coefficient of the sample is obtained. To improve the measuring accuracy, the bilinear interpolation of gray value is used to obtain the sub-pixel gray value. The results are compared with those obtained from the surface fitting algorithm. The experimental results demonstrate that the electrostrictive response of polyurethane increases with the introduction of barium titanate into polyurethane. And by using the DSCM, the measurement of the characteristic of electrostriction can be done quickly and accurately. The DSCM provides an effective tool for the evaluation of electrostrictive response.

乡村体育赛事赋能乡村振兴的SWOT分析——以贵州“村超”“村BA”为例

本文运用文献综述法、专家访谈法等研究方法,以贵州“村超”“村BA”为例,论证乡村体育赛事赋能乡村振兴的必要性,分析乡村体育赛事赋能乡村振兴的优势、劣势、机遇和挑战,对乡村体育赛事赋能乡村振兴的因素进行系统分析,建立SWOT矩阵模型,提出乡村体育赛事赋能乡村振兴的制定增长型(S-O)、实施弥补型(W-O)、拟定拓展型(S-T)和采取防御型(W-T)发展策略,从而推动乡村经济高质量发展,以期全面实现乡村振兴战略目标。

我国“村BA”发展的影响因素与路径分析——以贵州台盘“村BA”为例

采用文献资料法、访谈法等研究方法,以贵州台盘“村BA”为分析对象,探析“村BA”发展的影响因素,提出“村BA”发展路径。研究认为:“村BA”发展维度的结构体系包括政策引领、乡村治理、赛事文化、传播助推4个核心范畴,上位政策规划等9条范畴化语句,政策文件相继出台等17条概念化语句以及309条编码语句。其中,政策引领是“村BA”发展的基础支撑,乡村治理是“村BA”发展的内生动力,赛事文化是“村BA”发展的重要根基,传播助推是“村BA”发展的外在驱动。鉴于此,提出我国“村BA”发展路径:完善乡村赛事发展的保障机制,推动“村BA”健康发展;坚持农民主体地位,提升“村BA”自治能力;组建乡村篮球赛事联盟,推动“村BA”做大做强;打造农村体育赛事IP,建立以“村BA”为核心的产业集群。

“村BA”与乡村振兴文化建设的耦合发展研究——以贵州台盘村“村BA”为例

“村BA”是指在村里举行的以当地村民为运动主体的具有当地特色的篮球比赛。从运动员到奖品,“村BA”都与现代商业性体育文化形成鲜明相比。“村BA”虽以体育文化身份亮相乡村,却耦合乡村振兴过程中文化建设在物质、制度和精神三个层面发展需要,推动着乡村振兴过程中的文化建设。文章将从文化的物质、制度和精神三个层面解构“村BA”在乡村振兴过程中的耦合功能,多角度、多视点探讨乡村振兴过程中文化振兴的发展样式。

“村超”“村BA”助力贵州乡村体育产业高质量发展研究

基于乡村振兴的战略背景,厘清了“村超”“村BA”助力贵州乡村体育产业高质量发展的价值意蕴,剖析了“村超”“村BA”助力贵州乡村体育产业高质量发展的优势及现实困境,提出了“村超”“村BA”助力贵州乡村体育产业高质量发展的纾解路径,以期助推“十四五”时期贵州国民经济社会高质量发展.

乡土文化赋能和美乡村建设的实践论析——依据贵州省“村BA”的案例观察

乡土文化赋能和美乡村建设,既是落实乡土文化创造性转化与创新性发展的要求,也是建设宜居宜业和美乡村的重要手段。因此,将“如何实现乡土文化赋能和美乡村建设”作为核心问题,以贵州省台盘村“村BA”为个案研究,运用案例分析的方法,具体分析“村BA”留住“村味”、创新发展、主体协同的实践样态,明晰乡土文化+改善环境、乡土文化+产业平台、乡土文化+文明有序与和美乡村建设目标之间的耦合逻辑关系,最后从打造乡土文化竞争力、激活乡土文化再生产能力、激发乡土文化发展动力等方面总结乡土文化赋能和美乡村建设路径的经验启示。

新时代乡村体育发展路径与振兴战略研究——以贵州“村BA”现象为例

该文以贵州“村BA”现象为例,探讨了乡村体育发展的路径与振兴战略。首先,“村BA”不仅是一项体育赛事,还是乡村文化的体现,反映了乡村群众对体育文化的热爱与参与。“村BA”通过丰富多彩的体育活动和民族文化展示,吸引了大量观众和参与者,形成了独特的乡村文化氛围。其次,贵州“村BA”的成功举办显著提升了乡村群众的体育参与度,促进了体育活动的多样化和规范化,增强了村民的凝聚力和归属感。地方特色的体育文化挖掘和多渠道的推广传播,进一步扩大了乡村体育的影响力,推动了乡村经济的发展。培育乡村体育品牌和促进赛事的可持续发展是实现乡村振兴的重要举措。通过对贵州“村BA”现象的分析,该文为新时代乡村体育发展提供了宝贵的经验和启示。

从“村BA”的火爆出圈探析群众体育高质量发展路径

促进群众体育高质量发展是推动我国体育事业持续健康发展的重要组成部分,也是实现体育大国向体育强国转变的关键一环。“村BA”作为一种群众体育活动,在丰富了农民文化生活的同时,也促进了农村体育事业的发展,推动了全民健身的普及和发展。文章结合火爆全网的“村BA”的发展情况,通过分析其火爆出圈的原因,以及我国群众体育发展现状存在的问题,对群众体育高质量发展的路径进行了探讨,旨在促进群众体育更好发展。

叶面喷施6-BA对盐胁迫下不同种源黑果枸杞幼苗生理指标和光合特性的影响

以青海黑果枸杞和甘肃黑果枸杞实生苗为试验材料,分析不同浓度6-苄氨基腺嘌呤(6-BA)对盐胁迫下不同种源黑果枸杞幼苗生理指标、抗氧化系统和光合参数的影响。结果表明:(1)施加低、中浓度6-BA降低了无盐条件下两种黑果枸杞叶片和根中Na^(+)和Cl^(-)质量分数、过氧化氢(H_(2)O_(2))质量摩尔浓度、电解质外渗率,提高了抗坏血酸过氧化酶(APX)、谷胱甘肽还原酶(GR)、硝酸还原酶(NR)和ATP硫酸化酶(ATPS)活性,以及还原型谷胱甘肽(GSH)、氧化型谷胱甘肽(GSSG)、氮(N)、硫(S)质量分数和光合氮利用效率;高浓度6-BA对无盐条件下两种黑果枸杞上述指标却有相反的作用。(2)与青海黑果枸杞相比,甘肃黑果枸杞在盐胁迫下叶片中积累了更多的Na^(+)和Cl^(-),并遭受更大的氧化胁迫,表现为叶片中更高的H_(2)O_(2)质量摩尔浓度和电解质渗出率以及更低的光合参数。(3)受到盐胁迫后,青海黑果枸杞体内抗坏血酸过氧化物酶(APX)和谷胱甘肽还原酶(GR)活性高于甘肃黑果枸杞,但甘肃黑果枸杞的超氧化物歧化酶(SOD)活性更高。(4)与甘肃黑果枸杞相比,青海黑果枸杞叶中的氮和硫通过提高同化酶—硝酸还原酶(NR)和ATP硫酸化酶(ATPS)活性而积累更多,从而使叶片中还原型谷胱甘肽(GSH)质量分数显著提高。(5)低、中浓度6-BA有利于提高青海黑果枸杞和甘肃黑果枸杞氮硫同化效率、GSH质量分数以及APX和GR的活性,导致在无盐条件下光合作用增强,缓解了盐胁迫下光合作用的下降,限制了叶片中Na^(+)和Cl^(-)的质量分数,提高了光合氮利用效率;然而高浓度6-BA的应用对黑果枸杞的生长具有反作用;6-BA对青海黑果枸杞盐胁迫下各生理指标变化的影响比甘肃黑果枸杞更明显。因此,6-BA的施用,使青海黑果枸杞的NR和ATPS活性提高,增强了抗氧化防御系统的功能,缓解了盐胁迫引起光合作用减弱的现象。

地方特性与新山乡巨变——关于“村BA”纪实叙事的文化解码

在人本主义地理学者看来,人类生活在充满意义内涵的世界中,地方是人们对世界的一种主观态度和情感体验,一个地方的动态性、开放性、独特性与地方历史和特定地域人们的实践活动分不开。作为乡村振兴之写照的文化热点事件,台盘“村BA”球赛的火爆出圈与地方独特的精神生活密切相关,姚瑶所著的《村BA:观察中国式现代化的一个窗口--台盘村乡村振兴故事》正是对这种地方特性及乡村巨变的诗性书写与文化解码。

乡村体育赛事赋能乡村振兴路径研究——以贵州省“村BA”为例

发展乡村旅游是赋能乡村振兴的重要路径。以乡村体育旅游为代表的新型旅游形式展现了强劲动力。“现代体育运动+网络媒体宣传+跨域产业融合+经典民族文化+多元协同治理”是贵州省“村BA”火爆出圈的重要路径。同时,贵州省“村BA”还存在着赛事水平有限、资金支持缺乏、人才培养不足、党建引领不够、长效机制不全等问题,为此需要在赛事水平、资金支持、党建引领等方面持续改进。

Electromagnetic and microwave absorbing properties of W-type barium ferrite doped with Gd^(3+)

W-type barium ferrites doped with Gd^3＋,Ba1-xGdx（Zn0.3Co0.7）2Fe16O27（x = 0,0.05,0.10,0.15,0.20）,were prepared by a sol-gel method.The effects of Gd^3＋ substitution on their microstructure,electromagnetic properties and microwave absorptive behavior were analyzed.The XRD patterns showed the single phase of W-type barium ferrite when x ≤ 0.15.Microwave electromagnetic properties of samples were studied at the frequency range from 2 GHz to 18 GHz using a network analyzer（Agilent 8722ET）.The complex permittivity ε（ε＇,ε＇＇） increased gradually when x ≤ 0.10,but it decreased as x = 0.15.The real permeability（μ＇） decreased with the increase of Gd^3＋ content,while the imaginary permeability（μ＇＇） increased when x ≤ 0.10.All these reasons were discussed using the electromagnetic theory.Furthermore,the ferrite-epoxy compound coating materials with 80 wt.% of Ba0.9Gd0.1（Zn0.3Co0.7）2Fe16O27 were prepared to measure the microwave absorbing properties.The maximum of reflection loss（RL） reached about-27 dB and RL was below-10 dB in the frequency range of 8-18 GHz when the thickness was 1.92 mm.

Steam reforming of acetic acid over Ni-Ba/Al2O3 catalysts:Impacts of barium addition on coking behaviors and formation of reaction intermediates

The influence of barium addition to a Ni/Al2O3 catalyst on the reaction intermediates formed,the activity,resistance of the catalyst to coking,and properties of the coke formed after acetic acid steam reforming were investigated in this study.The results showed the drastic effects of barium addition on the physicochemical properties and performances of the catalyst.The solid-phase reaction between alumina and BaO formed BaAl2O4,which re-constructed the alumina structure,resulting in a decrease in the specific surface area and an increase in the resistance of metallic Ni to sintering.The addition of barium was also beneficial for enhancing the catalytic activity,resulting from the changed catalytic reaction network.The in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) study of the acetic acid steam reforming indicated that barium could effectively suppress the accumulation of the reaction intermediates of carbonyl,formate,and C=C functional groups on the catalyst surface,attributed to its relatively high ability to cause the gasification of these species.In addition,coking was considerably more significant over the Ba-Ni/Al2O3 catalyst.Moreover,the Ba-Ni/Al2O3 catalyst was more stable than the Ni/Al2O3catalyst,owing to the distinct forms of coke formed (carbon nanotube form over the Ba-Ni/Al2O3 catalyst,and the amorphous form over the Ni/Al2O3 catalyst).

Effect of barium on reducibility and activity for cobalt-based Fischer-Tropsch synthesis catalysts

Barium modified Co/Al2O3 catalysts were prepared by incipient wetness impregnation.The catalysts were characterized by XRD,TPD and DRIFTS.The catalytic activity for Fischer-Tropsch synthesis was measured in a continuously stirred tank reactor.It was found that small amounts of BaO（≤2 wt%） improved the cobalt reducibility,which led to more cobalt active sites on the catalyst surface,and then resulted in higher CO conversion and C5＋ selectivity.However,for the catalysts with high BaO loadings negative effects on the catalytic activity and selectivity for high hydrocarbons were observed because of low cobalt reducibility.

Deoxidation Behavior of Alloys Bearing Barium in Molten Steel

The deoxidation behaviors of alloys bearing barium in pipe steel were researched with MgO crucible under argon atmosphere in MoSi2 furnace at 1 873 K.The total oxygen contents of molten steel,the distribution,size and morphology of deoxidation products in the steel were surveyed.The metamorphic mechanism for deoxidation products of alloy bearing barium was also discussed.The results show that applying alloy bearing barium to the pipe steel,very low total oxygen contents can be obtained,and deoxidation products,which easily float up from molten steel,can be changed into globular shape and uniformly distributed in steel.The equilibrium time of total oxygen is about 25 min,and the terminal total oxygen contents range from 0.002 0%to 0.002 2% after treating with SiCa wire.The best deoxidizers are SiAlBaCa and SiAlBaCaSr.

Control on Crystal Forms of Ultrafine Barium Carbonate Particles and Study on its Mechanism

Barium carbonate particles were prepared by using homogeneous precipitation method and co-precipitation method respectively. Through adding different crystalline controlling modifiers, Barium carbonate particles in five different shapes including linear, needle-like, pillarlike, sphere-like and dumbbell-like were synthesized. These particles were characterized by SEM and XRD, and their synthetic mechanism was discussed in this paper.

Effectiveness of therapeutic barium enema for diverticular hemorrhage

AIM:To evaluate the effectiveness of barium impaction therapy for patients with colonic diverticular bleeding.METHODS:We reviewed the clinical charts of patients in whom therapeutic barium enema was performed for the control of diverticular bleeding between August2010 and March 2012 at Yokohama Rosai Hospital.Twenty patients were included in the review,consisting of 14 men and 6 women.The median age of the patients was 73.5 years.The duration of the followup period ranged from 1 to 19 mo(median:9.8 mo).Among the 20 patients were 11 patients who required the procedure for re-bleeding during hospitalization,6patients who required it for re-bleeding that developed after the patient left the hospital,and 3 patients who required the procedure for the prevention of rebleeding.Barium(concentration:150 w%/v%)was administered per the rectum,and the leading edge of the contrast medium was followed up to the cecum by fluoroscopy.After confirmation that the ascending colon and cecum were filled with barium,the enema tube was withdrawn,and the patient’s position was changed every 20 min for 3 h.RESULTS:Twelve patients remained free of rebleeding during the follow-up period(range:1-19mo)after the therapeutic barium enema,including 9men and 3 women with a median age of 72.0 years.Re-bleeding occurred in 8 patients including 5 men and 3 women with a median age of 68.5 years:4developed early re-bleeding,defined as re-bleeding that occurs within one week after the procedure,and the remaining 4 developed late re-bleeding.The DFI(disease-free interval)decreased 0.4 for 12 mo.Only one patient developed a complication from therapeutic barium enema(colonic perforation).CONCLUSION:Therapeutic barium enema is effective for the control of diverticular hemorrhage in cases where the active bleeding site cannot be identified by colonoscopy.