开发支出资本化与企业创新

以2007至2017年沪深A股上市公司为研究对象,本文考察了开发支出资本化对企业创新的影响。,实证结果研究发现,开发支出资本化比例与企业创新呈倒U型关系。且结论在稳健性检验之后依然成立。表明：当开发支出资本化比例低于临界值时,由于抑制了管理层通过削减研发投资以实现盈余目标的动机得到抑制,从而促进企业创新;当开发支出资本化比例高于临界值时,促使管理层基于声誉风险管理层为避免将已资本化金额转为费用对当期盈余造成的负面冲击,进行过度研发投资,从而阻碍企业创新。说明不同开发支出资本化比例下,管理层研发投资不同动机对企业创新产生非线性影响。结论在稳健性检验之后依然成立。进一步分析还发现：,开发支出资本化通过研发投资效率作用于企业创新,而且管理层面临的盈余公告压力越大,开发支出资本化对企业创新的非线性影响更为显著。资本化通过非效率研发投资,作用于企业创新;盈余公告压力越大,资本化与企业创新之间的倒U型关系越明显。     

IT engagement as a blessing and a curse? Examining its antecedents and outcomes in organizations

Information technology (IT) engagement is defined as a need to spend more time using IT. Practice-based examples show that IT engagement can have adverse effects in organizations. Although users can potentially get more work done through IT engagement, observations show that the users might jeopardize their well-being and hamper their work performance. We aimed to investigate this complexity in the research on IT engagement by examining its potential antecedents and outcomes in organizations. Considering the potentially mixed outcomes, we developed a model to examine the effects of IT engagement on personal productivity and strain. We also aimed to explain the antecedents of IT engagement by drawing on the collective expectations for IT use. In particular, we examined the extent to which normative pressure on IT use drives users’ information load and IT engagement. Finally, we sought to understand whether users’ attempts to avert dependency on IT use reduced their IT engagement. Several hypotheses were developed and tested with survey data of 1091 organizational IT users. The findings help explain the role of normative pressure as a key driver of IT engagement and validate the positive and negative outcomes of IT engagement in organizations.     

基于DISLab的两个热学实验设计

本文利用数字化信息实验系统,对大气压影响水的沸点实验和做功改变气体内能两个实验进行了创新设计,实现实验现象与数据显示、图像处理等多模显示同步。学生在实验操作过程中,通过对比实验现象和多模显示内容,能够更加容易地得出相应的实验结论,改变了传统实验中实验现象与数据分析分离的问题。     

Experiments on Cu-isotope fractionation between chlorine-bearing fluid and silicate magma: implications for fluid exsolution and porphyry Cu deposits

Hydrothermal fluid is essential for transporting metals in the crust and mantle. To explore the potential of Cu isotopes as a tracer of hydrothermal-fluid activity, Cu-isotope fractionation factors between Cl-bearing aqueous fluids and silicate magmas (andesite, dacite, rhyolite dacite, rhyolite and haplogranite) were experimentally calibrated. Fluids containing 1.75–14 wt.% Cl were mixed together with rock powders in Au₉₅Cu₅ alloy capsules, which were equilibrated in cold-seal pressure vessels for 5–13 days at 800–850°C and 2 kbar. The elemental and Cu-isotopic compositions of the recovered aqueous fluid and solid phases were analyzed by (LA-) ICP–MS and multi-collector inductively coupled plasma mass spectrometry, respectively. Our experimental results show that the fluid phases are consistently enriched in heavy Cu isotope (⁶⁵Cu) relative to the coexisting silicates. The Cu-isotope fractionation factor (Δ⁶⁵Cu_FLUID-MELT) ranges from 0.08 ± 0.01‰ to 0.69 ± 0.02‰. The experimental results show that the Cu-isotopic fractionation factors between aqueous fluids and silicates strongly depend on the Cu speciation in the fluids (e.g. CuCl(H₂O), CuCl₂^– and CuCl₃²⁻) and silicate melts (CuO_1/2), suggesting that the exsolved fluids may have higher δ⁶⁵Cu than the residual magmas. Our results suggest the elevated δ⁶⁵Cu values in Cu-enriched rocks could be produced by addition of aqueous fluids exsolved from magmas. Together with previous studies on Cu isotopes in the brine and vapor phases of porphyry deposits, our results are helpful for better understanding Cu-mineralization processes.     

提升就业能力:缓解大学生就业难的重要选择

高等教育大众化条件下的大学生就业形势日趋严峻,缓解大学生就业结构性矛盾的难题需要不断增强毕业生的就业能力。合理调适专业、坚持特色育人、强化就业指导是现行教育体制下提升大学生就业能力的有效举措。     

液压泵零流量压力急增故障的分析与排除

针对液压泵在试验中成批出现零流量压力急剧增大的故障现象,从液压泵的工作原理出发对其进行分析,找到了故障原因,并采取了相应的措施,使故障有效排除,从根本上解决了生产中的疑难问题.     

混凝土薄壁池体爆破方法研究

本文针对薄壁池体,从爆破工程实际出发以减小爆破公害、提高爆破效率为目的,提出适合薄壁池体的爆破新方法--"水土压爆破".通过分析论证、同常规方法的对比,可知新方法对于薄壁池体是爆破技术领域的一大进步.     

Mineralogy of the deep lower mantle in the presence of H2O

Understanding the mineralogy of the Earth''s interior is a prerequisite for unravelling the evolution and dynamics of our planet. Here, we conducted high pressure-temperature experiments mimicking the conditions of the deep lower mantle (DLM, 1800–2890 km in depth) and observed surprising mineralogical transformations in the presence of water. Ferropericlase, (Mg, Fe)O, which is the most abundant oxide mineral in Earth, reacts with H₂O to form a previously unknown (Mg, Fe)O₂H_x (x ≤ 1) phase. The (Mg, Fe)O₂H_x has a pyrite structure and it coexists with the dominant silicate phases, bridgmanite and post-perovskite. Depending on Mg content and geotherm temperatures, the transformation may occur at 1800 km for (Mg_0.6Fe_0.4)O or beyond 2300 km for (Mg_0.7Fe_0.3)O. The (Mg, Fe)O₂H_x is an oxygen excess phase that stores an excessive amount of oxygen beyond the charge balance of maximum cation valences (Mg²⁺, Fe³⁺ and H⁺). This important phase has a number of far-reaching implications including extreme redox inhomogeneity, deep-oxygen reservoirs in the DLM and an internal source for modulating oxygen in the atmosphere.     

肱动脉血压相关因素的研究

利用20天的时间,每天10:00到15:00随机抽查,测量本校1000名大学生(男女生各500人)左右侧肱动脉血压的差异性;测量江苏省徐州市醒狮居民小区居民500名(男女各250人),年龄在20至69岁之间,探究血压与年龄和性别之间的关系。在大学生组中,将测量所得的结果通过χ2检验,u检验,其p值均大于0.05;典型相关分析检验中,相关系数约为1,说明大学生左右肱动脉血压无显著差异。在居民组中,运用matlab 7.0对数据进行拟合,结果显示随年龄的增长,舒张压、收缩压均逐渐升高,且收缩压的增长要大于舒张压的增长,男性的脉压整体高于女性,大约在45岁之后,双方差异逐渐减小。     

新课程实施中的教师压力及其管理策略

在新课程实施过程中,课程理念的更新、教师角色的转换、教学范式的变革,给教师带来了前所未有的压力。持续不断的压力往往会引起教师心理上的过度紧张与焦虑,进而影响新课程的实施。因此,要对新课程实施中的教师压力给予充分的关注,并采取适当策略对其进行有效的管理,以真正实现教师与课程改革的共同成长。