Enhancing the stability of Ni Fe-layered double hydroxide nanosheet array for alkaline seawater oxidation by Ce doping

Electrocatalytic hydrogen production from seawater holds enormous promise for clean energy generation.Nevertheless,the direct electrolysis of seawater encounters significant challenges due to poor anodic stability caused by detrimental chlorine chemistry.Herein,we present our recent discovery that the incorporation of Ce into Ni Fe layered double hydroxide nanosheet array on Ni foam(Ce-Ni Fe LDH/NF)emerges as a robust electrocatalyst for seawater oxidation.During the seawater oxidation process,CeO_(2)is generated,effectively repelling Cl^(-)and inhibiting the formation of Cl O-,resulting in a notable enhancement in the oxidation activity and stability of alkaline seawater.The prepared Ce-Ni Fe LDH/NF requires only overpotential of 390 m V to achieve the current density of 1 A cm^(-2),while maintaining long-term stability for 500 h,outperforming the performance of Ni Fe LDH/NF(430 m V,150 h)by a significant margin.This study highlights the effectiveness of a Ce-doping strategy in augmenting the activity and stability of materials based on Ni Fe LDH in seawater electrolysis for oxygen evolution.

Double设计在对称化L_2-偏差下的均匀性

二水平部分因子设计在工农业生产、科学实验等领域得到广泛应用,因此有关二水平部分因子设计的研究一直是热点问题.最近,一种称为doubling的方法被用来构造二水平部分因子设计,特别是在构造分辨度为Ⅳ的设计时,这种方法是非常简单但很实用的方法,本文从均匀性的角度来研究double设计,进一步讨论doubling方法的实用性,利用对称化L_2-偏差作为均匀性的测度,发现double设计D(X)的均匀性与初始设计X的均匀性有着密切的联系,给出了double设计在对称化L_2-偏差下的下界.

Double设计在对称化L_2-偏差下两个下界的比较

从列平衡的角度出发,将设计的中心化L2-偏差、对称化L2-偏差、可卷L2-偏差分别用二次型和均衡模式表示,可分别得到两个下界,它们都适合用来评价正交设计的均匀性。以double设计的对称化L2-偏差为例,证明了这两种方法算出的下界是相等的。

Double设计在对称化L_2-偏差下的广义字长型

在工农业生产、科学实验等领域都广泛应用到二水平部分因子设计.最近,在构造二水平部分因子设计时一种称为doubling的方法被使用.特别是在构造分辨度为IV的设计时,doubling是非常简单但很实用的方法.本文利用对称化L2-偏差作为均匀性的测度,得到了double设计D(X)的对称化L2-偏差值与初始设计X的广义字长型之间的关系.利用上述关系,我们断定对于具有广义较小低阶混杂的初始设计X,其对应的double设计D(X)也应该具有较小的对称化L2-偏差值,也就是说,D(X)应该具有较好的均匀性.

Double perovskite oxides Sr_2Mg_(1-x)Fe_xMoO(6-δ) for catalytic oxidation of methane

The double perovskite oxides Sr2Mg1-xF exMoO6-δ were investigated as catalysts for the methane oxidation.The structural properties of catalysts were characterized in detail by X-ray diffraction,X-ray photoelectron spectroscopy and X-ray absorption spectroscopy.The catalytic property was strongly influenced by the Fe substitution.The relation between catalytic performance and the degree of Fe substitution was examined with regard to the structure and surface characteristics of the mixed oxides.The Fe-containing catalysts exhibited higher activity attributable to the possible（Fe2＋,Mo6＋） and （Fe3＋,Mo5＋）valency pairs,and the highest activity was observed for Sr2Mg0.2Fe0.8MoO6-δ.The enhancement of the catalytic activity may be correlated with the Fe-relating surface lattice oxygen species and was discussed in view of the presence of oxygen vacancies.

Effect of nitrite intercalated Mg-Al layered double hydroxides on mortar durability under Cl−and SO_(4)^(2-) coexisting environment

The aim of this paper is to investigate the effect of nitrite intercalated Mg-Al layered double hydroxides(Mg-Al LDH-NO_(2))on mortar durability under the coexisting environment of Cl−and SO_(4)^(2-).Cl−and SO_(4)^(2-) binding properties of Mg-Al LDH-NO_(2) in simulated concrete pore solutions,Cl−and SO_(4)^(2-) diffusion properties of mortars with Mg-Al LDHNO 2 were examined.The steel corrosion and resistance of mortar against SO_(4)^(2-) attack were also evaluated.The results indicate that Mg-Al LDH-NO_(2) can effectively adsorb the Cl−and SO_(4)^(2-) in simulated concrete pore solution,and inhibit the diffusion of Cl−and SO_(4)^(2-) into cement mortars.The presence of SO_(4)^(2-) can greatly affect the uptake amount of Cl−,and there is a coupled effect of Cl−and SO_(4)^(2-) on their penetration into mortar specimens.In addition,Mg-Al LDH-NO_(2) can greatly upgrade the resistance of mortars against SO_(4)^(2-) attack and well prevent the steel from corrosion.However,Cl−will aggravate the SO_(4)^(2-) attack and SO_(4)^(2-) can initially decrease and then increase the steel corrosion.

Desorption of Cl^(-) from Mg-Al layered double hydroxide intercalated with Cl^(-) using CO_(2) gas and water

Mg-Al layered double hydroxide intercalated with CO_(3)^(2-)(CO_(3)·Mg-Al LDH) is effective for treating HCl exhaust gas.HCl reacts with CO_(3)^(2-) in CO_(3)·Mg-Al LDH, resulting in the formation of Cl·Mg-Al LDH.We propose that CO_(2) can be used for the desorption of Cl^(-)from Cl·Mg-Al LDH to regenerate CO_(3)·Mg-Al LDH.Herein,we studied the desorption of a from CI-Mg-Al LDH by adding water to Cl·Mg-Al LDH and blowing CO_(2) into it.We also analyzed the effects of temperature and water addition speed on the desorption of CI^(-)from Cl·Mg-Al LDH.Our results show that the added water adhered to CI·Mg-Al LDH and that CO_(2) in the gaseous phase was dissolved in this adhered water,thus generating CO_(3)^(2-).Therefore,anion exchange occurred between CO_(3)^(2-) and Cl^(-)in the Cl·Mg-Al LDH,thus desorbing Cl^(-).

Promoting surface reconstruction of NiFe layered double hydroxides via intercalating[Cr(C_(2)O_(4))_(3)]^(3-)for enhanced oxygen evolution

Rationally manipulating surface reconstruction of catalysts for water oxidation,inducing formation and dynamic accumulation of catalytically active centers still face numerous challenges.Herein,the introduction of[Cr(C_(2)O_(4))_(3)]^(3-)into NiFe LDHs by intercalation engineering to promote surface reconstruction achieves an advanced oxygen evolution reaction(OER)activity.In view of the weak electronegativity of Cr^(3+) in[Cr(C_(2)O_(4))_(3)]^(3-),the intercalation of[Cr(C_(2)O_(4))_(3)]^(3-)is expected to result in an electron-rich structure of Fe sites in NiFe LDHs,and higher valence state of Ni can be formed with the charge transfer between Fe and Ni.The optimized electronic structure of NiFe-[Cr(C_(2)O_(4))_(3)]^(3-)-LDHs with more active Ni^(3+) species and the expedited dynamic generation of Ni^(3+) (Fe)OOH phase during the OER process contributed to its excellent catalytic property,revealed by in situ X-ray absorption spectroscopy,Raman spectroscopy,and quasi-in situ X-ray photoelectron spectroscopy.With the modulated electronic structure of metal sites,NiFe-[Cr(C_(2)O_(4))_(3)]^(3-)-LDHs exhibited promoted OER property with a lower overpotential of 236 mV at the current density of 10 mA cm^(-2).This work illustrates the intercalation of conjugated anion to dynamically construct desired Ni^(3+) sites with the optimal electronic environment for improved OER electrocatalysis.

Study on the Technique of Double-faced Embroidery on Chinese Palace Fans

Double - faced iso - object embroidery is carried out byusing the uneven intercalated stitch crafts of the parallel- lines stitch as a main body, being accompanied by oth-er stitch crafts and miscellaneous stitches, done on thesame textile material. This paper deals with the flower -bird double - faced embroidery fan of the Qing Dynasty,from pattern design, stitching formation and techniqueof color arrangement, describes the possible way of mak-ing double - faced embroidery with iso - object effectboth in the front and in the back.

New Pyrometer with Double Y-type Optical Fibers

Abstract: A new pyrometer, which can solve the affection of emissivity change in temperature measuring, has been developed by double Y - type optical fibers. The mathematical model of the new pyrometer is presented and the errors of the new pyrometer are analyzed.

Constraints on Estimation of Radius of Double Pulsar PSR J0737-3039A and Its Neutron Star Nuclear Matter Composition

The aspect of formation and evolution of the recycled pulsar（PSR J0737-3039 A/B） is investigated, taking into account the contributions of accretion rate, radius and spin-evolution diagram（- diagram） in the double pulsar system. Accepting the spin-down age as a rough estimate（or often an upper limit） of the true age of the neutron star, we also impose the restrictions on the radius of this system. We calculate the radius of the recycled pulsar PSR J0737-3039 A ranges approximately from 8.14 to 25.74 km, and the composition of its neutron star nuclear matters is discussed in the mass-radius diagram.

Double设计的几个结果

讨论了Double设计在对称化L2-偏差下的均匀性,给出了Double设计为均匀设计的充要条件,同时得到了Double设计的对称化L2-偏差的下界,来评价Double设计的均匀性,最后通过一个例子来验证理论结果。

基于双师课堂的教育见习、研习新模式建构与实践路径探析--以邢台学院双师课堂项目为例

地方院校应用型转型及新师范建设的背景下,创新教师教育专业实践教学模式、强化师范生实践能力培养已成为必然。双师课堂为地方院校创新教师教育教育见习、研习提供了新思路、新平台。邢台学院双师课堂项目,构建了“一核心两平台三主体四维度”,集教育见习与教育研习一体化的实践教学新模式。该模式围绕强化师范生实践能力培养核心目标,发挥地方政府、高校、基础教育三方主体协同创新优势,围绕“师德规范、教学实践、班级管理、教育研究”四维度内容,依托“智慧教室+现实教室”两平台开展“线上+线下”实践活动,探索教育见习+教育研习一体化的实践教学新路径。

A New Inversion Method of Sedimentary Strata For Deriving Double Parameters and Its Applications

The inverse problem of wave equation is the importance of study not only in seismic prospecting but also in applied mathematics. With the development of the research, the inverse methods of 1 - D wave equations have been trending towards the multiple parameters inversion . We have obtained an inverse method with double -parameter, in which medium density and wave velocity can be derived simultaneously. In this paper, to increase the inverse accuracy, the method is improved as follows. Firstly, the formula in which the Green Function is omitted are derived and used. Secondly, the regularizing method is reasonable used by choosing the stable function. With the new method, we may derive elastic parameter and medium density or medium density and wave velocity. Thus, lithology parameters for seismic prospecting may be obtained.After comparing the derived values from the new method with that from previous method, we obtain the new method through which substantially improve the derived accuracy . The new method has been applied to real depths inversion for sedimentary strata and volcanic rock strata in Chaoyanggou Terrace of Songliao Basin in eastern China. According to the inverse results,the gas - bearing beds are determlned.

江西省高职院校“双师型”教师队伍建设政策的实施成效研究--基于多期双重差分模型

党的十八大以来,党和国家出台系列政策,推动“双师型”教师队伍建设,推动职业院校采取校外引进、校内培养、定期轮训等多种形式扩大“双师型”教师队伍规模。本文使用多期双重差分模型,探讨江西省高职院校“双师型”教师队伍建设政策实施成效,探寻政策生效或失灵的原因,提出政策优化的建议。研究发现:高职院校“双师型”教师队伍建设政策的实施对不同教师群体均有促进效果,对高级职称“双师型”教师和青年“双师型”教师占比的提升具有显著作用。从政策异质性来看,“激励型”和“保障型”政策效果明显,“约束型”政策效果不显著。从年龄和职称结构来看,“激励型”政策对不同年龄和职称“双师型”教师队伍优化的效果明显,“保障型”政策的实施有效促进了青年“双师型”教师结构的优化。从异质性政策交互作用来看,“激励型”和“保障型”政策、“约束型”和“保障型”政策之间存在明显的替代效应。公办高职院校实施“双师型”教师队伍建设政策的成效更显著,工程技术类高职院校实施“双师型”教师队伍建设政策的成效与商科、卫生、师范类高职院校没有明显差异。

高职金融人才“岗课赛证创”综合育人模式功能价值与路径研究--基于“政、企、家、校”协同的视角

“岗课赛证创”综合育人模式的特点是以“点”为融入,匹配岗位需要;以“线”为逻辑,深化赛证融合;以“面”为拓展,培养创新能力。金融专业实践教学改革顺应“岗课赛证创”综合育人的发展趋势,面临数字化金融技能创新的紧迫形势,它是构建五位一体,拓展补充的实践教学体系的必然选择;是加强数字“双师型”师资队伍建设内在要求;是校企资源整合,场地设备更新的现实需要。“岗课赛证创”综合育人模式的实施路径是“课证”融通,加强政策的出台、“岗课”共设,促进企业的参与、“赛创”互促、重视家校的培养、“产教”并举,打造“双师型”师资。

职业教育“双师型”教师基本标准区域实施的比较研究--基于五省职业院校“双师型”教师认定标准

“双师型”教师认定标准是衡量职业院校师资队伍水平的准绳之一。基于甘豫赣桂皖五省区域层面的“双师型”教师认定试行标准的共性差异分析,发现各省在设计分层分类认定标准、强调多样化能力考察、突出成果导向、结合省域特点发展创新方面共性突出。也存在认定条件区域差异大、同类认定条件达成难度差异大、认定类目复杂等问题。基于分析提出扎根区域需求提高认定标准的科学性,围绕教师关键能力强化资源保障,借力双师分层定级提高职教教师社会认可度的建议思考。

职业教育“双师型”教师专业发展的伦理向度及行动策略

在职业教育步入新时代的背景下,教育部将师德考核作为“双师型”教师职业考核的第一标准,突出了职业伦理在“双师型”教师职业标准中的首要地位。发展职业伦理是“双师型”教师专业发展的内在诉求。根据“双师型”教师专业发展要求,从教学伦理、技术伦理和学术伦理三个向度进行深刻剖析,明确“双师型”教师专业发展各伦理向度的要求和内容。通过完善伦理培训体系与评价机制,发展教学伦理;深化校企合作与产教融合,发展技术伦理;加强组织与制度建设,发展学术伦理,从而有效促进“双师型”教师职业伦理发展。

培养创新创业能力的职业教育模式研究

如何更加高效地培养学生创新创业能力,探索出既不烦琐又可操作且广泛适用的职业教育模式,是现阶段各大高职院校亟须解决的重要课题。为进一步促进高职院校培养创新创业能力的职业教育模式改革与发展,对现有高职创新创业教育模式存在的弊端进行分析,提出“厚植学生创新创业观、完善高职院校创新创业教育体系、优化高职院校创新创业实践体系、建立健全创新创业能力培养评价机制”等策略,助力职业教育高质量发展,培养出理念先进、技术扎实、素养过硬的新时代复合型人才。

职业教育企业培训师培育的德日经验及启示

《国家职业教育改革实施方案》提出,为打造“双师型”教师队伍,职业院校相关专业教师原则上从具有3年以上企业工作经历并具有高职以上学历的人员中公开招聘。但如何从制度和机制上确保企业人员的准入、使用及专业水平,仍然是我国政策有效落地的实践难题。通过对职业教育发达国家德国企业培训师和日本职业培训指导员培育制度的研究发现,基于法律规定的企业培训师管理办法、促进企业培训师专业发展的培养与培训机制、建立稳定且动态调整的制度保障等经验,为我国优化“双师型”教师队伍建设、提高企业来源教师的专业化水平提供了有益启示:以立法形式确保教师的专业性地位与作用;以培养培训一体化促进教师专业发展;以制度性保障提升教师职业吸引力。