四氯化碳加氢Pt／C催化剂活性下降原因浅析

在FYX－1型1L高压反应釜上考察了Pt/C催化剂对四氯化碳加氢制氯仿反应性能的影响，结果表明，CCl4的转化率和CHCl3的选择性均达到95％－97％，但催化剂重复使用后，CCl4转化率明显下降，通过液氮容量吸附和原子吸收光谱法分析，其活性下降的原因可能是反应产生的氯离子与Pt/C催化剂发生了某种化学和物理吸附，氯和Pt形成了Cl-Pt中间体，部分氯占据了Pt/C催化剂的表面，从而导致催化剂活性下降。     

From aniline to phenol: carbon-nitrogen bond activation via uranyl photoredox catalysis

Carbon-nitrogen bond activation, via uranyl photoredox catalysis with water, enabled the conversion of 40 protogenetic anilines, 8 N-substituted anilines and 9 aniline-containing natural products/pharmaceuticals to the corresponding phenols in an ambient environment. A single-electron transfer process between a protonated aniline and uranyl catalyst, which was disclosed by radical quenching experiments and Stern-Volmer analysis, facilitated the following oxygen atom transfer process between the radical cation of protonated anilines and uranyl peroxide originating from water-splitting. ¹⁸O labeling and ¹⁵N tracking unambiguously depicted that the oxygen came from water and amino group left as ammonium salt. The 100-fold efficiency of the flow operation demonstrated the great potential of the conversion process for industrial synthetic application.     

QUANTUM CHEMICAL STUDIES ON A NEW ORGANOSULFUR REACTION MECHANISM

ＱＵＡＮＴＵＭＣＨＥＭＩＣＡＬＳＴＵＤＩＥＳＯＮＡＮＥＷＯＲＧＡＮＯＳＵＬＦＵＲＲＥＡＣＴＩＯＮＭＥＣＨＡＮＩＳＭＺｈｕＪｉｎ；ＣｈｅｎＹａ－ｌｉｎｇ（ＩｎｓｔｉｔｕｔｅｏｆＣｈｅｍｉｓｔｒｙ，ＡｃａｄｅｍｉａＳｉｎｉｃａ，Ｂｅｉｊｉｎｇ１０００８０...     

矩形微槽内水的流动沸腾换热及可视化实验研究

本实验以水为工质，对截面尺寸为0.4mm×0.4mm水平布置的不锈钢矩形微槽内流动沸腾进行换热特性和可视化研究.质量流速范围为G＝62.5～187.5kg/m2s，进口温度分别为Tin＝30、45、 60°C.实验结果表明，在较低干度下，换热系数随着干度的增加而增加；干度较大时，换热系数保持不变直至换热恶化.质量流速的增加使换热系数有较大增加，进口温度的变化对换热系数几乎没有影响.可视化研究发现低壁面过热度时，有大量气泡产生；在本实验范围内，微槽内沸腾的流型主要有塞状流和环状流两种.     

知识转移对企业创新能力的影响研究——网络中心性的调节作用

以我国集成电路产业及其创新网络为研究样本,开发知识转移、创新能力与网络中心性的测量量表,实证检验知识转移对企业创新能力的影响,以及网络中心性在其中所起的调节作用。研究结果表明,辅助型和互补型的知识转移对于企业渐进式创新能力和突破式创新能力都有显著的正向影响,但对比而言,互补型知识转移对突破式创新能力的正向影响更显著;辅助型知识转移对于渐进式创新的正向影响更显著。创新网络中心性在知识转移和创新能力之间起到正向的调节作用。     

丙烯酸甲酯的真空紫外光电离质谱研究

利用同步辐射光和反射飞行时间质谱,研究了丙烯酸甲酯9.0~15.5 eV能量范围的真空紫外光电离和光解离.实验测量丙烯酸甲酯的光电离质谱和解离碎片离子m/e=86(C4H6O+2), 85(C4H5O+2), 59(C2H3O+2), 58(C3H6O+), 55(C3H3O+), 42(C3H+6), 31(CH3O+), 27(C2H+3), 和15(CH+3)的光电离效率曲线.并利用量子化学从头算(G3),计算碎片离子的能级,推测它们的解离通道.计算的电离能和出现势与实验结果符合很好.结果表明,丙烯酸甲酯的光电离解离通道以单键断裂反应为主.     

明胶水溶液中银离子的光还原

利用紫外线辐射ＡｇＮＯ３明胶（ＣＨ３）２ＣＨＯＨ 水溶液制备了银纳米颗粒,并用吸收光谱和透射电镜跟踪研究了其形成过程．发现增大明胶和银离子浓度可以加速银颗粒的生成,其粒径随明胶浓度增大而减小,银颗粒的光还原过程属于准一级反应;明胶保护下的银纳米颗粒具有很高的稳定性．提出了ＡｇＮＯ３明胶（ＣＨ３）２ＣＨＯＨ水溶液中Ａｇ ＋ 的光还原及明胶对银颗粒的稳定机理     

Graphdiyne-based metal atomic catalysts for synthesizing ammonia

Development of novel catalysts for nitrogen reduction at ambient pressures and temperatures with ultrahigh ammonia (NH₃) yield and selectivity is challenging. In this work, an atomic catalyst with separated Pd atoms on graphdiyne (Pd-GDY) was synthesized, which shows fascinating electrocatalytic properties for nitrogen reduction. The catalyst has the highest average NH₃ yield of 4.45 ± 0.30 mg_NH3 mg_Pd⁻¹ h⁻¹, almost tens of orders larger than for previously reported catalysts, and 100% reaction selectivity in neutral media. Pd-GDY exhibits almost no decreases in NH₃ yield and Faradaic efficiency. Density functional theory calculations show that the reaction pathway prefers to perform at the (Pd, C1, C2) active area because of the strongly coupled (Pd, C1, C2), which elevates the selectivity via enhanced electron transfer. By adjusting the p–d coupling accurately, reduction of self-activated nitrogen is promoted by anchoring atom selection, and side effects are minimized.     

Laser-driven programmable non-contact transfer printing of objects onto arbitrary receivers via an active elastomeric microstructured stamp

Transfer printing, as an important assembly technique, has attracted much attention due to its valuable merits to develop novel forms of electronics such as stretchable inorganic electronics requiring the heterogeneous integration of inorganic materials with soft elastomers. Here, we report on a laser-driven programmable non-contact transfer printing technique via a simple yet robust design of active elastomeric microstructured stamp that features cavities filled with air and embedded under the contacting surface, a micro-patterned surface membrane that encapsulates the air cavities and a metal layer on the inner-cavity surfaces serving as the laser-absorbing layer. The micro-patterned surface membrane can be inflated dynamically to control the interfacial adhesion, which can be switched from strong state to weak state by more than three orders of magnitude by local laser heating of the air in the cavity with a temperature increase below 100°C. Theoretical and experimental studies reveal the fundamental aspects of the design and fabrication of the active elastomeric microstructured stamp and the operation of non-contact transfer printing. Demonstrations in the programmable transfer printing of micro-scale silicon platelets and micro-scale LED chips onto various challenging receivers illustrate the extraordinary capabilities for deterministic assembly that are difficult to address by existing printing schemes, thereby creating engineering opportunities in areas requiring the heterogeneous integration of diverse materials such as curvilinear electronics and MicroLED displays.     

三聚噻吩与富勒烯（C70）间光致电子转移的荧光猝灭研究

在施主/受主荧光系统中,荧光猝灭可用于研究光致电子的转移。当样品中各组分的吸收谱及相应荧光谱存在严重交迭时,荧光检测不可避免地会受到内滤效应及荧光材料吸收深度的影响,造成猝灭率虚高的赝象。本文就三聚噻吩/富勒烯混合液的光谱校正进行研究,以便于正确评估施主与受主材料间的光致电子转移。     

跨国公司战略管理知识转移机制的案例研究

通过典型单案例研究对跨国公司战略管理知识转移的机制进行探讨和建构,选取A公司的北京分公司作为研究对象,在文献综述的基础上,深挖案例证据,通过深层分析和归纳得出最后研究结论。研究结果最终揭示:隐性、复杂性和专有性三个知识特征,以及信任、文化距离和子公司的战略地位三个组织关系特征是战略管理知识转移的重要前因变量,而知识质量和吸收能力是子公司战略目标实现的重要中间变量,需要引起跨国公司及其子公司的重视。本案例构建的研究模型需要多案例研究以及实证研究的进一步检验和论证。     

国家科技创新体系下研究型大学的技术转移模式探讨

国家中长期科技发展规划明确提出了企业是创新主体,而大学尤其是研究型大学作为知识的重要创造源头,在以知识为主的经济中有着重要的作用．对大学在技术转移方面的问题进行较深入的探讨,以探索现阶段适合我国大学通过技术转移为社会经济作贡献的新模式．     

企业智力资本对渐进式和根本性技术创新影响的路径探究

通过文献研究与企业调研访谈探究企业智力资本与技术创新之间的路径关系.研究表明:企业智力资本对渐进式和根本性技术创新均具有显著正效应,组织资本通过内部隐性知识转移对渐进式技术创新产生影响;内部隐性知识转移受组织资本和关系资本影响显著,且组织资本的作用更强,外部隐性知识转移受人力资本和关系资本影响显著;而内部隐性知识转移仅对渐进式技术创新具有显著正效应,外部隐性知识转移对根本性技术创新具有显著正效应,同时,外部隐性知识转移受内部隐性知识转移的影响显著.研究结论为企业实施有效的智力资本积累和技术创新战略提供借鉴.     

卟啉类化合物电致发光性能研究进展

卟啉是一类具有优良光电性能的有机电致发光材料。无论是将卟啉掺杂还是引入高分子链段,都可以通过从主体材料到卟啉的能量转移获得饱和红光。本文对卟啉及其金属配合物在有机电致发光材料方面的研究做了综述。     

Unleash electron transfer in C–H functionalization by mesoporous carbon-supported palladium interstitial catalysts

The functionalization of otherwise unreactive C–H bonds adds a new dimension to synthetic chemistry, yielding useful molecules for a range of applications. Arylation has emerged as an increasingly viable strategy for functionalization of heteroarenes which constitute an important class of structural moieties for organic materials. However, direct bisarylation of heteroarenes to enable aryl-heteroaryl-aryl bond formation remains a formidable challenge, due to the strong coordination between heteroatom of N or S and transitional metals. Here we report Pd interstitial nanocatalysts supported on ordered mesoporous carbon as catalysts for a direct and highly efficient bisarylation method for five-membered heteroarenes that allows for green and mild reaction conditions. Notably, in the absence of any base, ligands and phase transfer agents, high activity (turn-over frequency, TOF, up to 107 h⁻¹) and selectivity (>99%) for the 2,5-bisarylation of five-membered heteroarenes are achieved in water. A combination of characterization reveals that the remarkable catalytic reactivity here is attributable to the parallel adsorption of heteroarene over Pd clusters, which breaks the barrier to electron transfer in traditional homogenous catalysis and creates dual electrophilic sites for aryl radicals and adsorbate at C2 and C5 positions. The d-band filling at Pd sites shows a linear relationship with activation entropy and catalytic activity. The ordered mesopores facilitate the absence of a mass transfer effect. These findings suggest alternative synthesis pathways for the design, synthesis and understanding of a large number of organic chemicals by ordered mesoporous carbon supported palladium catalysts.     

研发项目对大学技术转让合同影响的实证研究——以中国985工程高校为例

研发项目和科研经费是高校开展科研活动和技术转让的资源基础。采用教育部内部资料提供的22所"985工程"高校在1998-2010年的面板数据,构建研发项目的综合投入指标、研发项目的类型、科研经费的不同来源、专利活动对技术转移合同数量和合同金额影响的经验分析模型。研究发现,相同变量对合同数量影响的显著性要强于对合同金额的影响;政府资金和企业资金对技术转让合同的数量和金额均产生正向影响;专利申请和专利授权量对技术转让合同数量有显著正向影响,但是对合同金额的影响在统计意义上并不显著。研究结果为如何从资源配置的角度提高大学技术转让水平提供了有价值的政策启示。     

旗舰企业对本地企业知识转移的影响因素研究——基于全球制造网络的视角

从全球制造网络的视角系统构建了旗舰企业对本地企业知识转移的影响因素框架,丰富了以往对知识转移作用机制的认识。通过105家中国样本企业的实证研究表明:(1)旗舰企业知识转移强度、本地企业吸收能力、知识转移平台障碍是影响知识转移绩效的三个重要因素,其中旗舰企业的知识转移强度在双方知识交流、旗舰企业转移意愿与知识转移绩效间起中介作用;(2)双方联结方式对这三个因素影响知识转移绩效具有调制作用。相对于企业内联结,企业间联结方式下旗舰企业知识转移强度、本地企业吸收能力对知识转移绩效的正向效应减弱,知识转移平台障碍对知识转移绩效的负向效应增强。     

一些配位过渡金属或稀土连结的多钼酸化合物的合成、结构及性能研究（英文）

利用简单的手性有机配体L-酒石酸成功地合成出了一系列类似DNA螺旋构型的左、右旋的一维链状聚合物：{A[Mo2VIO4LnIII(H2O)6(C4H2O6)2]·4H2O}n (Ln = Sm, Eu, Gd, Ho, Yb, Y; C4H2O6 = L- 或 D-酒石酸； A = NH4 或 H3O)。通过水热法，巧妙地把传统的钼氧单核{MoO4}、双核{Mo2O7}以及{Mo8O26}等结构单元，通过有机配体配位的过渡金属单元交错地连接成零、一、二、三维的一系列结构新颖的化合物，这类化合物大多数具有可以容纳客体小分子的隧道或空穴，如 [Cu(4,4’-bpy)]2MoO4·2H2O，[Cu(4,4’-bpy)]2Mo2O7，[Cu(4,4’-bpy)(Hnic)(H2O)]2Mo8O26等。首次利用水热法合成出了含稀土的杂多酸类化合物，[Gd(H2O)3]3[GdMo12O42]·3H2O。该化合物是由Silverton-型的 [GdMo12O42]9- 阴离子和配位的Gd3+ 阳离子组成的。在[GdMo12O42]9- 离子中首次把顺磁性的钆(III)离子引入到该构型的中心，并且通过九配位的钆(III)离子把它们连接成具有介孔结构的三维网状化合物。该化合物的获得为今后合成类似化合物提供了一个很好的范例。在水热法合成出的化合物，[Cu2(C8H6N2)2(C7H6N2)]2[Mo8O26] 中，首次捕捉到喹喔啉的氧化产物苯并咪唑，证明了在水热条件下含氮的芳香杂环类的有机配体可以被二价铜氧化，其氧化产物进而作为配体直接与铜原子配位，最终形成新颖的上述化合物。     

组织的知识转移分析

本文提出了一个新的知识转移分析框架和方法。首先给出了"成功的知识转移"的概念和分析框架,接着提出了知识转移水平和知识转移效率的概念,并从不同的维度对知识转移水平和效率进行了划分,然后分别对它们进行了探讨。在此基础上,构建了组织知识转移的数学模型,给出了知识转移水平和效率的计算公式。     

Hierarchically porous monoliths based on low-valence transition metal (Cu,Co, Mn) oxides: gelation and phase separation

Hierarchically porous monoliths based on copper (Cu), cobalt (Co) and manganese (Mn) oxides with three-dimensionally (3D) interconnected macropores and open nanopores were prepared using metal bromides as precursors via a sol–gel process accompanied by phase separation. The difficulty of gelation for low-valence metal cation was overcome by introducing a highly electronegative Br atom near to the metal atom to control the rates of hydrolysis and polycondensation. The 3D interconnected macropores were obtained using appropriate polymers to induce phase separation. The domain sizes of macropores and skeletons can be controlled by reaction parameters such as concentration and/or average molecular weight of polymers, and the amount of hydrochloric acid. The crystalline metal oxide monoliths with their 3D interconnected macroporous structure preserved were obtained after heat treatment in air.