禁“塑”——政府：禁“塑”多部门联动

禁“塑”主题是环保，环保是全社会的事情。从政府职能来说，禁“塑”并不只是环保部门的工作，还牵涉到质检、工商、科技、环卫、卫生、旅游、交通、财政、税务、物价等部门。

再谈中国传统造型艺术之“雕”与“塑”

当今的“中国雕塑”是一个有很大包容性的立体造型艺术,包括城市公共环境中的大型造型作品,精致玲珑的牙雕玉器、收藏于书斋桌架上古朴儒雅的欣赏品、陈列于现代博物馆中前卫超前的展览品和画廊陈列出售的各种雕塑艺术家个人的作品等,这些艺术品,不论使用何种物质材料加工形成,都是通过艺术劳动创造的,具有人文文化内容和形式的艺术作品,汇聚形成了一个丰富多样、各具特色、精彩纷呈的立体艺术世界,同时也综合体现出立体造型艺术的文化研究价值和传承历史意义。

生物降解塑料在厨余垃圾堆肥中厌氧降解性能研究

选取4种典型生物降解塑料PLA、PBAT、PBS和淀粉混合物,通过自主搭建厌氧生物降解性能检测平台,进行为期290天的厨余垃圾堆肥中厌氧降解性能评估。进一步通过监测PLA、PBAT薄膜降解过程中形貌尺寸、失重、分子量和结构变化,研究了厌氧降解过程机制。研究表明4种生物降解塑料在厌氧厨余垃圾堆肥中发生不同程度降解,但矿化率变化趋势都是先快后趋于缓慢,其中PLA最快,然后是PBS和淀粉混合物,PBAT最慢,在290天后累积矿化率依次分别达到33.8%,27.3%,20.1%和12.7%。相同的是,无论PLA还是PBAT,都存在微生物酶催化氧化作用,进而促进降解;不同的是,PLA薄膜经历快速本体水解过程,而PBAT薄膜经历表面腐蚀降解过程。本工作为生物降解塑料大面积推广应用的环境安全性评价,以及回收并厌氧堆肥处理可行性提供科学依据。

“塑身减脂”体育课对超重女大学生体格焦虑的干预研究

"塑身减脂"体育课可减少脂肪和改善体格焦虑的大学生机体,提高自信心。选30名女大学生,按照不同条件随机分为实验组和对照组各15名。实验组将进行为期13周的"塑身减脂"特别设计课程,对照组也进行13周以身体素质教学内容为主的体育课程。用体格焦虑量表、身体自尊量表以及体重指数进行评估。结果表明,"塑身减脂"体育课可以有效地改善肥胖女大学生的体脂、体格焦虑和自身价值感。

浅析我国对外传播中的“塑他”策略

我国在对外传播中,除了关注"自塑"和"他塑"之外,还应化被动为主动,积极"塑他",即主动依据我国的价值标准塑造他国、他人形象,评说世界。

初做职业人的“塑身处方”

从学校走向社会,成为潇洒、自信的职场新人,是每个初涉社会者的渴望。然而,如何在全新的职场环境中恰当地表现出自己的自信与实力,迈出成功的第一步?下面设计的塑身方案,既浓缩了人力资源管理专家的精妙点评,又不乏职场过来人的经验之谈,兴许对做一名受人欢迎的职业新人有所启发。

盐田“塑垫防渗”区域的探讨

简析了江苏盐田的渗透情况及对海盐生产的影响,从实用和效益角度分析论证了“塑垫防渗”区域的重点应放于高级制卤区。

阻击“海洋PM2.5”必须“塑战速决”

第47个世界环境日,联合国环境规划署向全世界发起了对“塑”阻击战,并发出了“塑战速决”的号令.海洋,是这场狙击战的一个重要战场.当下,海洋污染令各国忧虑,塑料又是海洋的最大污染源.据统计,全球流入海洋的垃圾中80%以上是塑料垃圾.其中,微塑料是让大家捉摸不透的新“敌人”.

“塑”字的念法

以土搏制人物形像的动作叫做“su”，如“泥su”“su像”等，代表这种动作的字是“塑”。但是自从把这字用在工业上的名词里以后，许多人却读为“shuo”，如“shuo胶”“shao抖”。

Microstructural evolution and deformation mechanisms of superplastic aluminium alloys:A review

Aluminium alloy is one of the earliest and most widely used superplastic materials.The objective of this work is to review the scientific advances in superplastic Al alloys.Particularly,the emphasis is placed on the microstructural evolution and deformation mechanisms of Al alloys during superplastic deformation.The evolution of grain structure,texture,secondary phase,and cavities during superplastic flow in typical superplastic Al alloys is discussed in detail.The quantitative evaluation of different deformation mechanisms based on the focus ion beam(FIB)-assisted surface study provides new insights into the superplasticity of Al alloys.The main features,such as grain boundary sliding,intragranular dislocation slip,and diffusion creep can be observed intuitively and analyzed quantitatively.This study provides some reference for the research of superplastic deformation mechanism and the development of superplastic Al alloys.

Dynamic Phase Field Description on Ductile Fracture Process

In comparison to discrete descriptions of fracture process,the recently proposed phase field methodology averts the numerical tracking strategy of discontinuities in solids,which enables the numerical implement simplification.An implicit finite element formulation based on the diffuse phase field is extended for stable and efficient analysis of complex dynamic fracture process in ductile solids.This exhibited formulation is shown to capture entire range of the characteristics of ductile material presenting J2-plasticity,embracing plasticization,cracks initiation,propagation,branching and merging while fulfilling the basic principle of thermodynamics.Herein,we implement a staggered time integration scheme of the dynamic elasto-plastic phase field method into the commercial finite element code.The numerical performance of the present advanced phase field model has been examined through several classic dynamic fracture benchmarks,and in all cases simulation results are in good agreement with the associated experimental data and other numerical results in previous literature.

Modeling and characterization on electroplastic effect during dynamic deformation of 5182-O aluminum alloy

The coupling effects of electrical pulse,temperature,strain rate,and strain on the flow behavior and plasticity of 5182-O aluminum alloy were investigated and characterized.The isothermal tensile test and electrically-assisted isothermal tensile test were performed at the same temperature,and three typical models were further embedded in ABAQUS/Explicit for numerical simulation to illustrate the electroplastic effect.The results show that electric pulse reduces the deformation resistance but enhances the elongation greatly.The calibration accuracy of the proposed modified Lim−Huh model for highly nonlinear and coupled dynamic hardening behavior is not much improved compared to the modified Kocks−Mecking model.Moreover,the artificial neural network model is very suitable to describe the macromechenical response of materials under the coupling effect of different variables.

Effect of wire diameter compression ratio on drawing deformation of micro copper wire

A crystal plasticity finite element model was developed for the drawing deformation of pure copper micro wire,based on rate-dependent crystal plasticity theory.The impact of wire diameter compression ratio on the micro-mechanical deformation behavior during the wire drawing process was investigated.Results indicate that the internal deformation and slip of the drawn wire are unevenly distributed,forming distinct slip and non-slip zones.Additionally,horizontal strain concentration bands develop within the drawn wire.As the wire diameter compression ratio increases,the strength of the slip systems and the extent of slip zones inside the deformation zone also increase.However,the fluctuating stress state,induced by contact pressure and frictional stress,results in a rough and uneven wire surface and diminishes the stability of the drawing process.

Responses of soil enzyme and microbial community under co-loading of different microplastics and sulfamethoxazole

Polyamide/polyethylene(PA/PE)microplastics were injected into soil containing sulfamethoxazole(SMX)to investigate their combined effects on SMX removal,soil enzyme activity,and microbial communities.The results show that both PA and PE transiently increase SMX removal and inhibite the stimulation of microbial species diversity by SMX.The effect of PE is more significant.Meanwhile,PE combined with SMX increases the relative abundances of Actinobacteria and Pseudomonas,while PA combined with SMX decreases the relative abundances of Nocardioides and Streptomyces.In addition,PA/PE combined with SMX can increase dehydrogenase,urease,ammonia monooxygenase,and nitrate reductase activities in the soil while inhibiting the activity of laccase.Compared with PA combined with SMX,the activities of dehydrogenase,urease,ammonia monooxygenase,and laccase of PE combined with SMX increase by 9.82%,10.41%,8.07%,and 5.47%,while the activities of nitrate reductase and neutral phosphatase decrease by 1.47%and 6.78%.

Microstructural evolution and hot tensile behavior of Mg−3Zn−0.5Zr alloy subjected to multi-pass friction stir processing

The microstructures and hot tensile behaviors of ZK30 alloys subjected to single-and multi-pass friction stir processing(FSP)were systematically investigated.Following single-pass FSP(S-FSP),coarse grains underwent refinement to 1−2μm,with a distinct basal texture emerging in the stir zone(SZ).Additionally,second-phase particles were fragmented,dispersed,and partially dissolved.Multi-pass FSP(M-FSP)further enhanced the homogeneity of the microstructure,reduced texture intensity differences,and decreased the fraction of second-phase particles by 50%.Both S-FSP and M-FSP SZs demonstrated superplasticity at strain rates below 1×10^(−3)s^(−1)and at temperatures of 250−350℃.The S-FSP SZ exhibited an elongation of 390%at 250℃and 1×10^(−4)s^(−1),while the M-FSP SZ achieved an elongation of 406%at 350℃and 1×10^(−3)s^(−1).The superplastic deformation of SZ was co-dominated by grain boundary sliding(GBS)and the solute-drag mechanism in S-FSP and mainly by GBS in M-FSP.

Effects of heat treatment on microstructure and mechanical properties of ZK60 Mg alloy

The microstructure and mechanical properties of ZK60 Mg alloy were investigated under different solution treatments and artificial aging conditions. When as-cast ZK60 alloy was solution treated at 400 ℃for 10 h and artificially aged at 150 ℃, the volume fraction of precipitates increased with the aging time up to 30 h. When the as-cast ZK60 alloy was solution treated at 400 ℃ for 10 h and artificially aged at 200 ℃ for 15 20 h, the volume fraction of precipitates reached a peak value. Tensile test at room temperature showed that a high density of the second phase precipitates was beneficial to improving the strength and elongation. Solution treatment at 400 ℃ for 10 h and artificial aging at 150 ℃ for 30 h is considered the optimum heat treatment condition to obtain a good combination of strength and ductility.

STUDY ON FLOW STRESS OF 7022 ALUMINUM ALLOY SHEET UNDER DIFFERENT TEMPERATURES AND STRAIN RATES

Warm tensile tests for aluminum alloy 7022 sheet are held at different temperatures and strain rates. The range of temperature is 293-773 K and that of the strain rate is 0. 001-0.1 s^-1. The warm tensile properties,relations among temperature,strain rate,and the flow stress are discussed. Constitutive equations under the warm tension are obtained based on revised Hooke law and Grosman equation. It is concluded that flow stress declines with the increase of the temperature and the decrease of the strain rates. The elongation percentage increases with the increase of the temperature and the decrease of strain rate.

Influence of technical parameters on strength and ductility of AlSi9Cu3 alloys in squeeze casting

An orthogonal test was conducted to investigate the influence of technical parameters of squeeze casting on the strength and ductility of AISigCu3 alloys. The experimental results showed that when the forming pressure was higher than 65 MPa, the strength （ab） of A1Si9Cu3 alloys decreased with the forming pressure and pouring temperature increasing, whereas ab increased with the increase of filling velocity and mould preheating temperature. The ductility （6） by alloy was improved by increasing the forming pressure and filling velocity, but decreased with pouring temperature increasing. When the mould preheating temperature increased, the ductility increased first, and then decreased. Under the optimized parameters of pouring temperature 730 ℃, forming pressure 75 MPa, filling velocity 0.50 m/s, and mould preheating temperature 220 ℃, the tensile strength, elongation, and hardness of A1Si9Cu3 alloys obtained in squeeze casting were improved by 16.7%, 9.1%, and 10.1%, respectively, as compared with those of sand castings.

Superplasticity of AZ31 magnesium alloy prepared by friction stir processing

Microstructure and tensile behaviors of AZ31 magnesium alloy prepared by friction stir processing（FSP） were investigated.The results show that microstructure of the AZ31 hot-rolled plate with an average grain size of 92.0 μm is refined to 11.4 μm after FSP.The FSP AZ31 alloy exhibits excellent plasticity at elevated temperature,with an elongation to failure of 1050% at 723 K and a strain rate of 5×10-4 s-1.The elongation of the FSP material is 268% at 723 K and 1×10-2 s-1,indicating that high strain rate superplasticity could be achieved.On the other hand,the hot-rolled base material,which has a coarse grain structure,possesses no superplasticity under the experimental conditions.

Acetylation of Chinese bamboo flour and thermoplasticity

Chinese bamboo flour was chemically modified by acetylation with acetic anhydride by using trichloroacetic acid as an activation agent and the optimized condition for acetylation of bamboo flour was determined as the trichloroacetic acid amount 6.0 g per 1.5-g bamboo flour, ultrasosonication duration 40 min and the reaction time 1 h at 65℃. The composition, microstructure and thermal behavior of acetylated bamboo flour were preliminarily characterized by FT-IR, DSC and SEM etc. The acetylated bamboo flour can be molded into sheets at 130℃ and 10 MPa, indicating the modified bamboo flour possesses thermalplastic performance.