Study on production of liquid hydrocarbon fuels from sorbitol and mannitol

在温和条件下研究了氢碘酸还原生物质基多元醇制备液体燃料的过程,使用气相色谱质谱仪(GC-MS)和红外光谱仪(FT-IR)分析了产物组成。结果表明,山梨醇和甘露醇为原料制备的液体产物中主要成分是C_(12)H_(16)、C_(12)H_(18)、C_(12)H_(20)、C_(12)H_(22)和C_(18)H_(26)等烃类物质。通过与碱的醇溶液反应将副产物碘代烷转化为烃,经旋转蒸发和减压蒸馏获得纯净的高碳烃产品。山梨醇、甘露醇以及二者混合物制备出的高碳烃的产率分别是81.1%、73.2%和77.3%。本研究获得的高碳烃产品是一种有前景的液体燃料,其含水量为0.1%,密度为0.83~0.84 g·mL~(-1),含氧量为2.0%~2.2%,热值均高于42 MJ·kg~(-1)。This paper describes the process of sorbitol and mannitol conversion to liquid heavier hydrocarbons via reduction with hydroiodic acid under mild reaction conditions. The compositions of the obtained products were analyzed using gas chromatography mass spectrometer( GC-MS) and Fourier transform infrared spectrometer( FT-IR). It is found that the products obtained from C6 polyols were mainly C_(12)H_(16),C_(12)H_(18),C_(12)H_(20),C_(12)H_(22) and C_(18)H_(26). The yields of heavier hydrocarbons from sorbitol,mannitol,and the mixture of sorbitol and mannitol were 81. 1%,73. 2%,and 77. 3%,respectively.To obtain pure hydrocarbon fuels,the obtained crude oil was treated with potassium hydroxide in an alcohol solution followed by rotary evaporation and vacuum distillation. The final liquid hydrocarbons obtained have a water content of 0. 1%,densities of 0. 83 ~ 0. 84 g·mL~(-1),oxygen content of 2. 0% ~2. 2%,and heating values > 42 MJ·kg~(-1) at room temperature,which is potentially a good transportation fuel for diesel replacement.国家自然科学基金项目(21276214

灾难冲击与我国最优财政货币政策选择

本文通过引入政府生产性支出拓展了包含灾难冲击的新凯恩斯DSGE模型,数值分析表明,相对于不含政府生产性支出的灾难冲击模型,该模型能够更好地拟合中国宏观经济波动等基本特征。在此基础上,本文分别在规则行事与相机抉择两种情形下对比分析了我国面对灾难冲击时的最优财政货币政策选择问题,研究发现:(1)应对灾难冲击时,相对于相机抉择,规则行事造成的经济福利损失较低;(2)政府生产性支出可以在一定程度上降低灾难冲击对消费和产出等宏观经济变量的影响,但同时会弱化债务对灾难冲击的吸收作用;(3)引入通货膨胀惩罚(或厌恶)后政府可以更多地倚重于债务发行来吸收外部不利冲击,从而缓解相机抉择下的时间不一致性问题,减少经济福利损失。国家社科基金项目“预期灾难冲击、宏观经济波动与中国财政货币政策工具选择研究”(批准号:16BJL028)；国家自然科学基金面上项目“罕见灾难风险与资产定价:理论拓展与基于我国股市实证研究”(批准号:71471154)的资助

超竞争环境下的组合战略:理论分析与泉州实例

自20世纪80年代初竞争战略学说问世以来,学界在通用单一战略与组合战略哪一种更能提高组织绩效方面始终没有达成共识。随着相关领域学者对企业成功或失败的经验教训在战略高度上的不断探究,学界对组合战略的认识不断深入,对组合战略的研究取得了阶段性成果。本文综述了组合战略的理论来源和研究成果,在此基础上进行简要总结和评判,采用福建泉州鞋服产业的数据,论证组合战略与企业绩效之间的关系,为我国企业进行战略决策提供科学的理论依据和管理借鉴

产业集群嵌入性与供应链协同——基于泉州鞋服产业的实证研究

运用福建省泉州市鞋服产业的数据,论证产业集群嵌入性与供应链协同之间的关系,研究结论显示:(一)产业集群嵌入性因素对于企业内部和外部资源整合的供应链协同机制具有不同程度的影响。集群内企业之间的经济嵌入性对供应链协同机制将产生促进作用;集群内的社会体制嵌入性对企业内部整合的供应链集成行为的影响不显著,但是社会体制嵌入性对企业外部整合的供应链协同行为具有积极的促进作用。(二)产业集群嵌入性因素对于供应链的整体绩效具有不同程度的影响。经济嵌入性对供应链绩效没有产生显著的影响,而社会体制嵌入性对供应链绩效具有积极的影响。(三)企业在进行内部和外部资源整合时,如果采用供应链协同机制,将有利于提升供应链的整体绩效

高校校园商业活动现状调查与分析

伴随着我国经济的飞速发展,商业发展大潮已经渗入高校校园,越来越多的大学生开始接触并参与校园的商业活动。本文借助调查问卷对我国高校校园商业活动的发展现状以及对大学生自身成长的影响进行了探究,并较有针对性地提出了一些意见和建议,希望有益于校园商业活动的健康发展

A Positive Analysis of the Relationship Between Corporate Governance and Performance:On Chinese Listed Companies in Competitive Industry

运用深沪两市126家竞争性行业上市公司2002年的数据,从股权结构、董事会结构和高管激励等内外两种治理机制综合考虑了我国公司治理与公司绩效之间的关系。认为多元化股东、外部董事比例和高管激励是公司治理最为重要的三个因素,是影响公司绩效最为显著的变量;第一大股东是否为法人股、独立董事的作用、是否在国外上市对公司绩效没有显著的影响作用。This paper samples 126 listed companies in competitive industries in 2002 to verify the relationship between corporate governance and performance from internal and external governance mechanism.It turns out that decentralized ownership,higher outside director ratio and higher managers' incentives have positive effect on corporate performance,and that whether the top owner is juridical person,the independent director ratio and whether the companies are listed outside of mainland(dont) have significant effect on corporate performance

Hippo信号通路:器官大小与组织稳态调控器

复杂机体如何控制器官大小是发育生物学最基本问题之一,其调控机制的解析也是生命科学领域长期存在的一大难题。Hippo信号通路是21世纪初利用果蝇遗; 传学研究发现并命名的,它可以通过调控细胞增殖、凋亡和干细胞的自我更新与分化,在器官大小决定、组织稳态维持与重塑等生命活动过程中发挥关键作用。由于; Hippo信号通路在物种间高度保守,它的发现为人们研究生物个体器官发育大小及再生的调控机制提供了可能,这是利用果蝇遗传学研究解决重大科学问题的又; 一个经典范例。在过去的十几年中,针对Hippo信号通路的研究逐渐成为国际上又一新兴的研究热点

Topography-induced symmetry transition of droplets on quasi-periodically patterned surfaces

Quasi-periodic structures of quasicrystals yield novel effects in diverse systems. However, there is little investigation on employing quasi-periodic structures in morphology control. Here, we show the use of quasi-periodic surface structures in controlling the transition of liquid droplets. Although surface structures seem random-like, we find that on these surfaces, droplets spread to well-defined 5-fold symmetric shapes and the symmetry of droplet shapes spontaneously restores during spreading, hitherto unreported in the morphology control of droplets. To obtain physical insights into these symmetry transitions, we conduct energy analysis and perform systematic experiments by varying the properties of both liquid droplets and patterned surfaces. The results show the dominant factors in determining droplet shapes to be surface topography and the self-similarity of the surface structure. Quantified results of the droplet spreading process show distinct dynamics from the spreading experiments on periodically micropatterned surfaces. Our findings significantly advance the control capability of the droplet morphology. Such a quasi-periodic patterning strategy can offer a new method to achieve complex patterns, and may be used to model patterns in the study of rough surfaces

Experimental study on effect of Changrun Formula in regulating expression of AQP3 and AQP9 in colon mucosa of functional constipation rats

目的:观察肠润方对功能性便秘模型大鼠结肠黏膜AQP3、AQP9表达的影响,探究其调控AQP3、AQP9表达的分子机制。方法:60只SD大鼠随机分为空白组、模型组、阳性对照组(麻仁丸组)、肠润方组、肠润方联合P38MAPK抑制剂SB203580组。用复方地芬诺酯制造大鼠便秘模型,采用免疫组织化学及实时荧光定量PCR(q RT-PCR)检测大鼠便秘模型近端及远端结肠黏膜AQP3、AQP9的表达;Western Blot检测信号传导通路相关分子P38MAPK及P-P38MAPK的表达。结果:造模成功后,模型组近端结肠黏膜AQP3表达较空白组明显上升,而远端结肠黏膜AQP9表达较空白组明显下降(t值分别为3.148和7.069,P值均0.05)。肠润方联合P38MAPK抑制剂SB203580治疗后,近端结肠黏膜AQP3 m RNA水平显著上升(t=5.922,P0.05). The level of AQP3 m RNA in proximal colonic mucosa was significantly increased(t=5.922, P<0.01), and AQP9 m RNA was significantly decreased in distal colonic mucosa(t=4.038, P<0.01); The relative expression of P-P38/P38 protein was significantly decreased(t=19.419, P<0.01). Conclusion: The therapeutic action ofChangrun Formula on functional constipation rat models might through inhibiting the expression of AQP3 in proximal colon, and accelerating on expression of AQP9 in distal colon, and the regulating mechanism might relate with the inhibition on P38 MAPK and AKT phosphorylation.福建省自然科学基金项目(No.2012D043)~

SPATIAL PLANNING: GOVERNMENT AND MARKET

王富海(中国城市规划学会理事,学会学术工作委员会副主任委员,深圳市蕾奥城市规划设计咨询有限公司董事长,教授级高级城市规划师,本论坛主持人):多年来,我国城乡规划的创新与改革一直在进行当中。"新常态"形势的到来令其由过去的"量变积累"走到了"质变突破"的关口,为此,业界围绕变革已经进行了多角度、多路径的探讨。党的十八届三中全会提出了"建立空间规