学术自由与学术规范

学术自由是学术形成与发展的必要条件，已有的学术规范又为新的学术提供了对象与基础。二者对学术具有同样重要的意义。学术是自由探索与遵循规范的矛盾与辩证统一。     

高等教育的学术自由与学术自治--兼论中国高等教育学术权力的提高

学术自由与学术自治是高等教育中最悠久的传统 ,也是最古老的命题。关于这一命题的论争自其诞生之日起就一直没有停止过。甚至从某种意义上它影响着高等教育的进程。与这一对概念相联系的是学术权力问题 ,这同样是当前中国高等教育发展中一个值得给予充分关注的命题。一学术自由、学术自治是高等教育中颇为重要且相互联系的两个概念。下面我们从联系与区别的角度首先对学术自由与学术自治这对概念进行辨析 ,然后对学术自由与学术自治的享有与限制进行探讨。(一 )学术自由与学术自治的辨析传统的学术自由指的是大学学者 (包括教师和学生 )可…     

知识生产·国家控制·学术自由——学术自由的哲学解析

学术自由的确立根源于知识生产的个体性和社会性矛盾,前者奠定了学术自由合法性的观念基础,后者则决定了学术自由的制度形态。学术自由史实际上就是从观念到制度的发展历史,在这个过程中,国家利益与知识社会价值的博弈决定了学术自由可能的范围和限度。     

高等教育产业性与公益性的矛盾冲突及其协调

高等教育的产业性和公益性是高等教育本身所具有的特性,是相互联系的。一方面,根据系统论原理,两者应该是相互统一的;另一方面,高等教育的产业性和公益性是高等教育的两种不同性质,因此,可能是相互制约甚至是相互矛盾的。矛盾冲突之一,高等教育产品中的私人产品和...     

学术自由变迁中的矛盾辨析

在学术自由变迁的历史长河中,由于受到来自宗教、政府、企业甚至大学内部的妨碍,学术自由的发展面临着诸多矛盾.主要表现在:大学自治与学术自由并非总是一致的,而这种不一致可能会造成对学术自由的压制;大学对学者的刚性管理以及学术资本主义的风行,使得学术研究往往为功利所左右;大学内部的专业化发展造成学术共同体的分裂以及学科壁垒的出现,阻碍了学者在学术领域中自由交流和研究权利的实现;享有学术自由和承担学术责任之间由于“度”的缺失而产生失衡的状态.解决这些矛盾,需要站在学术价值追求和责任担当的基点上,实现积极的学术自由.     

英国大学与工业关系的国内研究

我们今天研究英国高等教育，最重要的一点就是要研究它在和工业直接结合方面取得的经验和教训．它直接关系到科学技术是否能转化为生产力，关系到高等教育在现代科技社会的地位、职能及其作用的转换。本文主要从英国大学与工业关系的历史发展、两者合作模式及合作中的矛盾与冲突等方面就国内部分研究资料进行粗浅的评析，以期引起更多、更深层次的思考和研究。     

美国大学学术权力与行政权力冲突的案例探析

学术权力和行政权力是存在于现代大学中的两种基本权力,在对美国密苏里大学堪萨斯城分校发生的学术权力和行政权力冲突的真实案例进行回溯分析的基础上,认为大学自治、学术自由和终身教职的制度设计是解决冲突的基本前提;大学教授的良知与责任感是解决冲突的必要条件;权力制衡的大学治理结构是解决冲突的组织保障。     

蔡元培校长的学术自由观与自由学术观

蔡元培校长是中国著名的教育家,他的学术自由观念帮助他在任北京大学校长期间将北大发展为中国最好的大学.北京大学自此一直保留着学术自由的传统并且受益于此.然而,很少有人注意到蔡元培先生的学术自由观念是建立在他的自由学术观念的基础之上的.他是中国大学历史上少有的几位具有鲜明的自由学术和自由教育思想的校长之一.通过对他的自由学术以及自由教育思想的发掘,有助于我们正确认识自由学术和自由教育在高等教育中的作用.     

学术型企业家:美国研究型大学教师学术创业角色冲突与化解北大核心

1980年,《拜杜法案》颁布后,教师学术创业成为美国研究型大学的基本运作形式并持续至今。教师参与学术创业后,其角色从学者转变为学术型企业家,原有的学者角色与企业家角色产生了角色冲突。究其原因,主要有学术文化与创业文化不兼容、默顿规范与企业家规范冲突、学者角色与企业家角色的认知差异。角色冲突主要表现在角色认同冲突、整合冲突以及投入冲突三方面。面对教师学术创业中的角色冲突,美国研究型大学通过赋能中介组织以缓冲角色矛盾,鼓励跨界协作以增进角色理解,创建角色层次结构以优化角色比重。     

玛莎·努斯鲍姆自由教育新意蕴辨析

自由教育是欧洲高等教育成功核心因素之一,也是美国高等教育傲视全球的文化资本,其重要性可见一斑。美国大学自由教育思想的发展,是各派观点相互冲突、交流、对话和创新的过程。玛莎·努斯鲍姆的自由教育思想既有别于古典自由教育,也与保守派自由教育针锋相对,因为她对自由教育守正出新、观点鲜明,赋予其新意蕴。在努斯鲍姆看来,自由教育意蕴之新在于三个方面:目的是培养世界公民;内容是培养人类共同的人性,而人性不是抽象的概念,具体包括理性、情感能力和叙事想象力;实践落实在设置人文学科和多元化课程,并实施苏格拉底式教学。     

Effects of Post-weld Heat Treatment on Microstructure,Mechanical Properties and the Role of Weld Reinforcement in 2219 Aluminum Alloy TIG-Welded Joints

In as-welded state, each region of 2219 aluminum alloy TIG-welded joint shows diff erent microstructure and microhardness due to the diff erent welding heat cycles and the resulting evolution of second phases. After the post-weld heat treatment, both the amount and the size of the eutectic structure or θ phases decreased. Correspondingly, both the Cu content in α-Al matrix and the microhardness increased to a similar level in each region of the joint, and the tensile strength of the entire joint was greatly improved. Post-weld heat treatment played the role of solid solution strengthening and aging strengthening. After the post-weld heat treatment, the weld performance became similar to other regions, but weld reinforcements lost their reinforcing eff ect on the weld and their existence was more of an adverse eff ect. The joint without weld reinforcements after the post-weld heat treatment had the optimal tensile properties, and the specimens randomly crack in the weld zone.     

The First Phase of the SRIF Industrialized Base in ＂West Area＂ Has Been Put into Operation

After nearly two years＇ tense construction, the first phase of industrialized base of Shenyang Research Institute of Foundry （SRIF）, located at the Tiexi Casting and Forging Industrial Park in the west of Tiexi District, has now been completed and formally put into operation.     

新型的治疗阿尔茨海默氏症药物(1-二甲基磷酰基-2,2,2-三氯)-乙基-1-醇烟酸醋对体外神经细胞的作用

目的: 观察本实验室合成的一种治疗阿尔茨海默氏症(AD)的药物(1-二甲基磷酰基-2, 2, 2 -三氯)-乙基^-1-醇烟酸醋(NMF),对体外培养的皮层神经细胞活性的影响以及对海人藻酸(KA)所致的神经损伤的保护作用。方法: 采用体外培养皮层神经元的方法,解剖分离 15 d胚胎小鼠皮层神经细胞, 接种于 96孔板,48 h 后加药并培养 72 h,以 MIT 法 观察 NMF 对小鼠皮层神经细胞活性的影响;同时将接种于 24 孔板的细胞预先给予 NMF,d 3 时加或不加KA处理后,以台盼蓝染色鉴别并计数死、活细胞,可得出细胞的存活率。结果: NMF 明显促进胎鼠皮层神经元活性,其中 NMF1、0. 1、10nmol·L^-1促进神经元活性增殖率分别高达 34.7%、37.4%、36. 7%, NMF 明显促进正常胎鼠皮层神经元存活卒,与对照组比较,10nmol·L^-1 NMF 对皮层神经元的存活率分别提高 39.3%、73.5%。 NMF能显著 对抗 KA 所致的神经元损伤,与 KA 损伤组相比, NMF0.1、10、10nmol·L^-1对损伤皮层神经元的保护率分别为 77.30%、80.10%、84.15%。结论: NMF 明 显促进胎鼠皮层神经元的洁性、提高正常皮层神经元,的存活卒,并能有效地保护KA所致的神经元损伤,提示 NMF 是一种很有潜力的治疗 AD 的药物。     

THERMODYNAMICS STUDY ON THE DECOMPOSITION OF CHROMITE WITH KOH

Institute of Process Engineering, Chinese Academy of Sciences, China, has proposed a method for oxidative leaching of chromite with potassium hydroxide. Understanding the mechanism of chromite decomposition, especially in the potassium hydroxide fusion, is important for the optimization of the operating parameters of the oxidative leaching process. A traditional thermodynamic method is proposed and the thermal decomposition and the reaction decomposition during the oxidative leaching of chromite with KOH and oxygen is discussed, which suggests that chromite is mainly destroyed by reactions with KOH and oxygen. Meanwhile, equilibrium of the main reactions of the above process was calculated at different temperatures and oxygen partial pressures. The stable zones of productions, namely, K2CrO4 and Fe2O3, increase with the decrease of temperature, which indicates that higher temperature is not beneficial to thermodynamic reactions. In addition, a comparison of the general alkali methods is carried out, and it is concluded that the KOH leaching process is thermodynamically superior to the conventional chromate production process.     

INFLUENCE OF HEAT TREATMENT ON DAMPING BEHAVIOUR OF THE MAGNESIUM WROUGHT ALLOY AZ61

The effect of isochronal heat treatments for 1h on variation of damping, hardness and microstructural change of the magnesium wrought alloy AZ61 was investigated. Damping and hardness behaviour could be attributed to the evolution of precipitation process. The influence of precipitation on damping behaviour was explained in the framework of the dislocation string model of Granato and Lücke.     

Three-Dimensional Growth of Coherent Ferrite in Austenite: A Molecular Dynamics Study

Coherent second phase often exhibits anisotropic morphology with specifi c orientations with respect to both the second and the matrix phases. As a key feature of microstructure, the morphology of the coherent particles is essential for understanding the second-phase strengthening eff ect in various industrial alloys. This letter reports anisotropic growth of coherent ferrite from austenite matrix in pure iron based on molecular dynamics simulation. We found that the ferrite grain tends to grow into an elongated plate-like shape, independent of its initial confi guration. The fi nal shape of the ferrite is closely related to the misfi t between the two phases, with the longest direction and the broad facet of the plate being, respectively, consistent with the best matching direction and the best matching plane calculated via the Burgers vector content(BVC) method. The strain energy calculation in the framework of Eshelby's inclusion theory verifi es that the simulated orientation of the coherent ferrite is energetically favorable. It is anticipated that the BVC method will be applicable in analysis of anisotropic growth and morphology of coherent second phase in other phase transformation systems.     

Effect of Rare Earth Doping on Impedance,Modulus and Conductivity Properties of Multiferroic Composites:0.5(BiLa_xFe_(1-x)O_3)–0.5(PbTiO_3)

The Lanthanum-doped bismuth ferrite–lead titanate compositions of 0.5(Bi LaxFe1-xO3)–0.5(Pb Ti O3)(x = 0.05,0.10,0.15,0.20)(BLxF1-x-PT) were prepared by mixed oxide method.Structural characterization was performed by X-ray diffraction and shows a tetragonal structure at room temperature.The lattice parameter c/a ratio decreases with increasing of La(x = 0.05–0.20) concentration of the composites.The effect of charge carrier/ion hopping mechanism,conductivity,relaxation process and impedance parameters was studied using an impedance analyzer in a wide frequency range(102–106Hz) at different temperatures.The nature of Nyquist plot confirms the presence of bulk effects only,and non-Debye type of relaxation processes occurs in the composites.The electrical modulus exhibits an important role of the hopping mechanism in the electrical transport process of the materials.The ac conductivity and dc conductivity of the materials were studied,and the activation energy found to be 0.81,0.77,0.76 and 0.74 e V for all compositions of x = 0.05–0.20 at different temperatures(200–300 °C).     

Using Finite Element and Contour Method to Evaluate Residual Stress in Thick Ti-6Al-4V Alloy Welded by Electron Beam Welding

This work was to reveal the residual stress profile in electron beam welded Ti-6Al-4V alloy plates(50 mm thick) by using finite element and contour measurement methods.A three-dimensional finite element model of 50-mmthick titanium component was proposed,in which a column–cone combined heat source model was used to simulate the temperature field and a thermo-elastic–plastic model to analyze residual stress in a weld joint based on ABAQUS software.Considering the uncertainty of welding simulation,the computation was calibrated by experimental data of contour measurement method.Both test and simulated results show that residual stresses on the surface and inside the weld zone are significantly different and present a narrow and large gradient feature in the weld joint.The peak tensile stress exceeds the yield strength of base materials inside weld,which are distinctly different from residual stress of the thin Ti-6Al-4V alloy plates presented in references before.     

Microstructures and Tensile Properties of Ultrafine-Grained Ni–(1–3.5) wt% SiC_(NP) Composites Prepared by a Powder Metallurgy Route

Silicon carbide nanoparticle-reinforced nickel-based composites(Ni–Si CNP),with a Si CNPcontent ranged from1 to 3.5 wt%,were prepared using mechanical alloying and spark plasma sintering.In addition,unreinforced pure nickel samples were also prepared for comparative purposes.To characterize the microstructural properties of both the unreinforced pure nickel and the Ni–Si CNPcomposites transmission electron microscopy(TEM) was used,while their mechanical behavior was investigated using the Vickers pyramid method for hardness measurements and a universal tensile testing machine for tensile tests.TEM results showed an array of dislocation lines decorated in the sintered pure nickel sample,whereas,for the Ni–Si CNPcomposites,the presence of nano-dispersed Si CNPand twinning crystals was observed.These homogeneously distributed Si CNPwere found located either within the matrix,between twins or on grain boundaries.For the Ni–Si CNPcomposites,coerced coarsening of the Si CNPassembly occurred with increasing Si CNPcontent.Furthermore,the grain sizes of the Ni–Si CNPcomposites were much finer than that of the unreinforced pure nickel,which was considered to be due to the composite ball milling process.In all cases,the Ni–Si CNPcomposites showed higher strengths and hardness values than the unreinforced pure nickel,likely due to a combination of dispersion strengthening(Orowan effects) and particle strengthening(Hall–Petch effects).For the Ni–Si CNPcomposites,the strength increased initially and then decreased as a function of Si CNPcontent,whereas their elongation percentages decreased linearly.Compared to all materials tested,the Ni–Si CNPcomposite containing 1.5% Si C was found more superior considering both their strength and plastic properties.     

Directional Growth of Tin Crystals Controlled by Combined Solute Concentration Gradient Field and Static Magnetic Field

A new method was introduced to achieve directional growth of Sn crystals. Microstructures in liquid(Pb)/liquid(Sn) diffusion couples were investigated under various static magnetic fields. Results show that the β-Sn crystals mainly reveal an irregular dendritic morphology without or with a relatively low static magnetic field(B0.3 T). When the magnetic field is increased to 0.5 T, the β-Sn dendrites close to the final stage of growth begin to show some directional character. With a further increase in the magnetic field to a higher level(0.8–5 T), the β-Sn dendrites have an enhanced directional growth character, but the dendrites show a certain deflection. As the magnetic field is increased to 12 T, the directional growth of the β-Sn dendrites in the center of the couple is severely destroyed. The mechanism of the directional growth of the β-Sn crystals and the deflection of the β-Sn crystals with the application of static magnetic field was tentatively discussed.