Enhancing MXene-based supercapacitors:Role of synthesis and 3D architectures

MXene has been the limelight for studies on electrode active materials,aiming at developing supercapacitors with boosted energy density to meet the emerging influx of wearable and portable electronic devices.Despite its various desirable properties including intrinsic flexibility,high specific surface area,excellent metallic conductivity and unique abundance of surface functionalities,its full potential for electrochemical performance is hindered by the notorious restacking phenomenon of MXene nanosheets.Ascribed to its two-dimensional(2D)nature and surface functional groups,inevitable Van der Waals interactions drive the agglomeration of nanosheets,ultimately reducing the exposure of electrochemically active sites to the electrolyte,as well as severely lengthening electrolyte ion transport pathways.As a result,energy and power density deteriorate,limiting the application versatility of MXene-based supercapacitors.Constructing 3D architectures using 2D nanosheets presents as a straightforward yet ingenious approach to mitigate the fatal flaws of MXene.However,the sheer number of distinct methodologies reported,thus far,calls for a systematic review that unravels the rationale behind such 3D MXene structural designs.Herein,this review aims to serve this purpose while also scrutinizing the structure–property relationship to correlate such structural modifications to their ensuing electrochemical performance enhancements.Besides,the physicochemical properties of MXene play fundamental roles in determining the effective charge storage capabilities of 3D MXene-based electrodes.This largely depends on different MXene synthesis techniques and synthesis condition variations,hence,elucidated in this review as well.Lastly,the challenges and perspectives for achieving viable commercialization of MXene-based supercapacitor electrodes are highlighted.

Embedding aligned nanofibrous architectures within 3D-printed polycaprolactone scaffolds for directed cellular infiltration and tissue regeneration

Three-dimensional(3D) printing provides a promising way to fabricate biodegradable scaffolds with designer architectures for the regeneration of various tissues.However,the existing3D-printed scaffolds commonly suffer from weak cell-scaffold interactions and insufficient cell organizations due to the limited resolution of the 3D-printed features.Here,composite scaffolds with mechanically-robust frameworks and aligned nanofibrous architectures are presented and hybrid manufactured by combining techniques of 3D printing,electrospinning,and unidirectional freeze-casting.It was found that the composite scaffolds provided volume-stable environments and enabled directed cellular infiltration for tissue regeneration.In particular,the nanofibrous architectures with aligned micropores served as artificial extracellular matrix materials and improved the attachment,proliferation,and infiltration of cells.The proposed scaffolds can also support the adipogenic maturation of adipose-derived stem cells(ADSCs)in vitro.Moreover,the composite scaffolds were found to guide directed tissue infiltration and promote nearby neovascularization when implanted into a subcutaneous model of rats,and the addition of ADSCs further enhanced their adipogenic potential.The presented hybrid manufacturing strategy might provide a promising way to produce additional topological cues within 3D-printed scaffolds for better tissue regeneration.

“新工科”背景下建筑设计人才“3+3+3”培养模式的建构

“新工科”国家战略的推动下,我国高等院校建筑人才培养面临新的挑战,建筑设计人才培养体系、培养质量与“新工科”建设愿景仍存在差距。该研究借鉴新加坡高等教育发展历程以及新加坡国立大学建筑设计人才培养内涵,探析如何在“新工科”背景下推动建筑设计人才培养模式的建构,以培养主体、培养途径、培养层级三要素为建筑设计人才培养框架,创新性提出“3+3+3”多层级建筑人才培养模式,以期为“新工科”战略的实施提供高素质建筑设计人才保障。

3D MXene architectures as sulfur hosts for high-performance lithium-sulfur batteries

Lithium-sulfur batteries(LSBs)are one of the most promising energy storage devices because of their high theoretical energy density;however,inherent issues including poor electrical conductivity and severe dissolution of S and its discharged products hinder their practical applications.MXenes have metallic conductivity,ultra-thin two-dimensional(2D)structures,rich surface functional groups,and macrostructural adjustability and have been widely used to design advanced sulfur hosts.3D network structures assembled by 2D MXene nanosheets have shown superior performance for improving reaction kinetics,accommodating and dispersing sulfur at the micro-/nanoscale,and capturing polysulfides due to their porous interconnected structure.Herein,the applications of MXene architectures related to 2D layered structures,3D multilayered structures,and 3D spherical structures as sulfur hosts are reviewed.The structure-performance relationship,challenges for current designs,and opportunities for future 3D architectures for LSBs are also analyzed.

GA_(3)处理影响菠菜性别及其株型发育

赤霉素(gibberellic acids,GAs)是一种重要的植物激素,但其对菠菜生长发育的影响尚未系统报道.以菠菜亚属PI647862为材料,研究了外源赤霉素(GA_(3))处理后对菠菜的性别转换、开花时间、花粉活力及植株发育等重要性状的影响.结果表明,用质量浓度为25 mg/L的GA_(3)对2叶期菠菜进行处理后,约13%的菠菜雌株转换为雄株,且转换株的花粉数目、形态及活力均和对照无显著差异.但是,转换雄株的开花时间显著早于对照雄株.研究结果也表明,GA_(3)处理后菠菜植株的高度、叶面积及叶柄长度均显著高于对照植株.进一步分析发现,株高的增加是由于节间细胞纵向伸长所导致的,叶面积的增加是叶细胞面积增加引起的.GA_(3)可诱导菠菜雌株发生雄性化转变,促进菠菜早花,同时促使株高、叶面积和叶柄长度也显著增加.研究结果为全面探究GA_(3)对于菠菜性别转换和株型发育的影响奠定了基础.

Service Model and Architecture for Beyond 3G System

Beyond 3G (B3G) system, the future mobile communication system, is envisioned as a user-centric, open, and convergent information infrastructure capable of providing personalized services. It is extremely important to develop service models and architectures for B3G system. A three-dimension service model is proposed. The dimensions are identified as service support scope, service capability definition, and adaptive feature elements. Then, the hierarchical service architecture for B3G is introduced. The enabling technologies for B3G service architecture are discussed in this paper, such as Virtual Home Environment (VHE), service support environment, service openness, distributed computing, intelligent technology, and profile.

Multi-source data-based 3D digital preservation of large scale ancient chinese architecture:A case report

The 3D digitalization and documentation of ancient Chinese architecture is challenging because of architectural complexity and structural delicacy.To generate complete and detailed models of this architecture,it is better to acquire,process,and fuse multi-source data instead of single-source data.In this paper,we describe our work on 3D digital preservation of ancient Chinese architecture based on multi source data.We first briefly introduce two surveyed ancient Chinese temples,Foguang Temple and Nanchan Temple.Then,we report the data acquisition equipment we used and the multi-source data we acquired.Finally,we provide an overview of several applications we conducted based on the acquired data,including ground and aerial image fusion,image and LiDAR(light detection and ranging)data fusion,and architectural scene surface reconstruction and semantic modeling.We believe that it is necessary to involve multi-source data for the 3D digital preservation of ancient Chinese architecture,and that the work in this paper will serve as a heuristic guideline for the related research communities.

Seismic Imaging and 3D Architecture of Yongle Atoll of the Xisha Archipelago, South China Sea

Yongle atoll in the Xisha(Paracel) Archipelago is an isolated carbonate platform developed on Precambrian metamorphic and Mesozoic volcanic rocks since the early Miocene. To identify the 3D stratigraphic architecture and evolution of this platform, 13 high-resolution seismic profiles and shallow-to-deep water multi-beam data were processed and analyzed to reveal seismic facies, sequence boundary reflectors, seismic units, and platform architecture. Nine types of seismic facies were recognized based on their geometry, which included seismic amplitude, continuity, and termination patterns;additionally, six reflections, i.e., Tg, T60, T50, T40, T30, and T20, were identified in the Cenozoic strata. Five seismic units, SQ1(lower Miocene), SQ2(middle Miocene), SQ3(upper Miocene), SQ4(Pliocene), and SQ5(Quaternary), were identified from bottom to top across the platform. The platform grew rapidly in the middle Miocene and backstepped in the late Miocene–Pliocene. Here, we discuss the developmental characteristics and evolution of the Yongle Atoll, in combination with drilling wells, which can be divided into four stages: the initiation stage in the early Miocene, the flourishing stage in the middle Miocene, the partial-drowning stage in the late Miocene–Pliocene, and modern atoll in the Quaternary.

Facet Regulation of Fe_(2)O_(3) via Nanoarray Architecture to Enable High Faradic Efficiency for Electrocatalytic Nitrogen Fixation

We propose a facile facet regulation enabled by nanoarray architecture to achieve a high faradic efficiency of Fe_(2)O_(3) catalyst for NRR. The a-Fe_(2)O_(3) nanorod arrays (NAs) were directly grown on carbon cloth (CC) with specific (104) facet exposure. The highly exposed (104) facets provide abundant unsaturated Fe atoms with dangling bonds as nitrogen reduction reaction catalytically active sites. In addition, the NAs architecture enables the enhanced electrochemical surface area (ECSA) to fully manifest the active sites and maintain the mass diffusion. Thus, the selectively exposed (104) facets coupled with the high ECSA of NAs architecture achieve a high FE of 14.89% and a high yield rate of 17.28 μg h^(-1) cm^(-2). This work presents an effective strategy to develop highly efficient catalytic electrodes for electrochemical NRR via facet regulation and nanoarray architecture.

A Porous 3D Supramolecular Architecture of Cd(II) Complex with Water Clusters as Pillars

A supramolecular complex of Cd（II） with 1D water tapes as pillars[Cd2（dpa）2（phen）2（H2O）2]·6H2O 1 （H2dpa = diphenic acid, phen = phenanthroline）, has been synthesized and characterized by elemental analysis, IR spectroscopy, and single-crystal X-ray diffraction analysis. The crystal is of triclinic, space group P1^- with a = 9.7029（4）, b = 11.9601（5）, c = 12.1788（4） A, α = 71.6990（10）, β = 71.8740（10）, γ = 74.4680（10）°, V = 1252.39（8） A^3, C52H48Cd2N4O16, Mr = 1209.76, Z= 1, Dc = 1.604 g/cm^3,μ = 0.925 mm^-1, F（000） = 612, R = 0.0679 and wR = 0.2514 for 3870 observed reflections （I 〉 2σ（I））. Two intramolecular Cd（II） centers of this complex are encircled by two dpa^2- ligands forming an 18-membered ring, which is further assembled into a pillared three-dimensional （3D） supramolecular architecture through the synergetic effect of intermolecular face-to-face π…π stacking and weak O-H…O hydrogen-bonding interactions. Moreover, this complex exhibits photoluminescence with the main emission bands located at about 456 nm upon excitation at 355 nm in the solid state at room temperature.

ZTE Shows Compliance with the MSF Release 3 Architecture

July 23,2007,Shenzhen,China -ZTE Corporation,a leading global provider of telecommunications equipment and network solutions,announced today that after extensive tests,its IMS product portfolios support the MultiService Forum (MSF) R3 "NGN Guidelines" and comply with the MSF Release 3 Architecture. ZTE,one of the most active members of MSF,began its Global Multiservice Interoperability (GMI) testing at Verizon’s lab in Waltham,Massachusetts in October 2006.

Architecture and Implementation of 3D Engine Based on WebGL

As the progress of 3D rendering technology and the changes of market demand, the 3D application has been widely used and reached as far as education, entertainment, medical treatment, city planning, military training and so on. Its trend is gradually changed from client to web, and so many people start to research the 3D graphics engine technology on the web. WebGL and HTML5 rise in recent years and WebGL solves two problems of interactive 3D application on the web perfectly. Firstly, it implements the interactive 3D web application by JavaScript without any browser plug-in components. Secondly, it makes graphics rendering using the underlying graphics hardware, which is united, standard and cross-platform OpenGL interface. However, it is very difficult for 3D application web programmer to understand multifarious details. Therefore, a 3D engine based on WebGL comes into being. The paper consults the existing 3D engine design idea, architecture and implementation experience, and designs a 3D graphics engine based on WebGL and Typescript.

Integrated Web Architecture Based on Web3D, Flex and SSH

Focusing on the problems occurred in traditional 2D image-word-based web applications, the author put forward con-cept of integrating Web3D, Flex and SSH technologies to create advanced “3D Virtual Reality & RIA” web application architecture, researched mechanisms of their architectures, and implemented their integration and communication & interaction: Flex and Struts2 via XML, Flex and Spring & Hibernate via BlazeDS, Flex and Web3D via JavaScript. The practice has shown that the integrated web architecture based on Web3D, Flex and SSH is effective and valuable.

郑州地铁3号线二期建筑方案研究与设计实践

从郑州地铁3号线二期四座车站建筑设计方案展开论述,对方案变化过程、设计重难点等进行了分析,并就建设过程中发生的主要问题及解决方案进行了归纳总结,提出可供后续其他地铁线路建设推广的主要经验与建议。

3-Tiers模式的办公自动化系统WUOA的设计与实现

为保证系统提供更好的客户服务、更快的响应，采用3-Tiers模型作为WUOA的软件体系结构;同时，用组件技术设计实现了WUOA中间层的全部软件功能。但3-Tiers结构中，组件在应用服务器与客户机之间的频繁信息传送，必然导致网络瓶颈问题。笔者提出了“虚拟”应用服务器的概念，设计了适用于OA的虚拟应用服务器VOA-APP，根据组件的使用频度、特征，适度地将组件分布在网络节点和客户机上，在组件分布的基础上，VOA-APP完成组件的实时发布与更新，较好地解决了组件集中与分散分布的协调问题。

在WWW上开发的3-Tiers应用系统

以金融行业为例，通过介绍３ － Ｔｉｅｒｓ 应用结构和 Ｗｉｎｄｏｗｓ Ｃ Ｇ Ｉ原理，对运用 Ｗｅｂ 技术、数据库技术开发３ － Ｔｉｅｒｓ 应用系统的方法的可行性和实用性，进行了研究和论证．

城市公园绿地区域PM_(2.5)-O_(3)复合污染空间分异特征研究——以北京奥林匹克森林公园为例

城市绿地能够改善城市区域环境污染进而提高人居环境质量。以北京奥林匹克森林公园绿地为例,选定典型植物群落结构、群落类型及景观环境样点,基于多年连续动态持续测定并选取典型年度数据(2020年),分析和阐释该公园绿地区域PM_(2.5)、O_(3)及PM_(2.5)-O_(3)复合污染空间分异特征。结果表明,公园绿地不同群落结构区域的PM_(2.5)浓度,乔灌草/乔灌/乔草结构低于灌草/草本地被结构;不同群落类型区域的PM_(2.5)浓度,常绿针叶型/针阔叶混交型/落叶阔叶型低于草本地被/灌丛;不同典型景观环境中,复层群落结构/双层群落结构/滨水植物群落/滨水广场区域的PM_(2.5)浓度要低于单层群落结构。试验中,不同群落结构、类型以及景观环境区域的O_(3)浓度均高于100μg·m^(-3)且样点间未呈现显著差异;以PM_(2.5)-O_(3)复合污染值为主要参数的空气质量评价值(AQI)达到“中度污染”等级,此结果值得进一步关注。以期为基于循证设计的功能型城市绿地规划设计及更新优化提供基础科学依据。

基于Web的3-Tier客户/服务器体系的应用系统开发研究

文章对比了传统客户／服务器体系、2－TierWeb应用体系以及3－TierWeb应用体系的优、缺点，经过对KIVAKDS／AnS应用软件的研究，提出了使用KIVA开发3－TierWeb应用系统的开发模型和策略，以及如何使用第三方调试工具（BorlandJbuilder）调试应用逻辑。