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Efficient hydrolysis of hemicellulose to furfural by novel superacid SO_4H-functionalized ionic liquids

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Green Energy & Environment 2019年第1期4卷 49-55页

作者： wei Hui yan Zhou yan Dong Zhi-Jun Cao Fei-Qiang He Min-Zhong cai Duan-Jian Tao College of Chemistry and Chemical engineering Institute of Advanced Materials Jiangxi Normal University

Novel superacid SO_4H-functionalized ionic liquids(SFILs) were designed and prepared in this work. The catalytic activities of SFILs were evaluated in xylan hydrolysis and xylose dehydration to produce furfural. Combined with the results of acid strength of SFILs characterized by solid-state ^(31)P MAS NMR, it was found that the catalytic performance of SFILs was positively correlated to their acid strength. The superacid SFIL [Ch-SO_4H][CF_3SO_3] displayed the best catalytic performance with more than 80% yield of furfural, and it was also obviously superior to usual SO_3H-functionalized acidic ILs, mineral liquid acids, and acidic resin Amberlyst-15 catalysts in catalytic activity under optimized conditions. In addition, the superacid SFIL [Ch-SO_4H][CF_3SO_3] could be easily separated from reaction system and reused at least five times without obvious decrease.

关键词： Superacid Ionic liquids Hemicellulose Hydrolysis Furfural

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磷酸钙陶瓷的热稳定性和显微结构

天津大学学报（自然科学与工程技术版） 2004年第4期37卷 345-348页

作者：蔡舒王彦伟李金有李鸿祥姚康德天津大学材料科学与工程学院先进陶瓷与加工技术教育部重点实验室天津300072 天津大学高分子材料研究所天津300072

用沉淀法和机械化学法合成不同Ca与P摩尔比的羟基磷灰石,考察Ca与P摩尔比对合成羟基磷灰石热稳定性和烧结体显微结构的影响.分别采用X射线衍射、红外光谱和扫描电镜分析合成粉体及烧结体的相组成和显微结构.结果表明:Ca与P摩尔比略大于... 详细信息

用沉淀法和机械化学法合成不同Ca与P摩尔比的羟基磷灰石,考察Ca与P摩尔比对合成羟基磷灰石热稳定性和烧结体显微结构的影响.分别采用X射线衍射、红外光谱和扫描电镜分析合成粉体及烧结体的相组成和显微结构.结果表明:Ca与P摩尔比略大于1.67的HA在烧结过程中有少量CaO形成,可有效抑制HA的分解,提高其高温稳定性;CaO晶粒可以钉扎晶界,抑制晶粒长大,但阻碍烧结.随Ca与P摩尔比减小,烧结体中晶粒尺寸增大.Ca与P摩尔比小于1.60的HA粉体,在1100℃下完全分解为β TCP相,烧结终止,继续升高温度,因β TCP相向α TCP转变伴随体积膨胀,导致裂纹产生.含碳酸根的HA的高温稳定性较差,烧结体中存在较多气孔.

关键词：磷酸钙陶瓷热稳定性显微结构沉淀法机械-化学法摩尔比生物材料

Pt25Rh/TaC界面特性的第一性原理研究

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原子与分子物理学报 2024年第5期41卷 144-152页

作者：左元华于晓华荣菊冯晶张志伟魏燕蔡宏中胡昌义昆明理工大学材料科学与工程学院昆明650093 昆明贵金属研究所昆明650221

铂铑(PtRh)合金具有优良的高温力学性能,是目前最具潜力的航天发动机推力器喷管材料之一.研究表明,进一步提升PtRh合金的高温性能,能有效延长航天飞行器的服役寿命.本研究利用第一性原理、materials Studio软件,研究了TaC热障涂层与Pt2... 详细信息

铂铑(PtRh)合金具有优良的高温力学性能,是目前最具潜力的航天发动机推力器喷管材料之一.研究表明,进一步提升PtRh合金的高温性能,能有效延长航天飞行器的服役寿命.本研究利用第一性原理、materials Studio软件,研究了TaC热障涂层与Pt25Rh高温合金的界面特性和结合机制.结果表明,TaC的热膨胀系数与Pt25Rh较为接近,比同类热障涂层具有更优的界面匹配性和结合力,既可作为单独的防护层使用,也可作为粘结层使用.此外,由于Ta-C,Pt-C和Rh-C键的电荷转移能力均强于Ta-Pt和Ta-Rh键,TaC与Pt25Rh合金的最稳定结合位置为孔位的Pt25Rh(111)/TaC(111)C,其界面粘附功为6.202 J/m^(2).本研究可为PtRh合金的热防护提供借鉴.

关键词：高温合金热障涂层第一性原理界面结构结合机制

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盐岩蠕变特征对井筒形变量的影响规律

西安石油大学学报（自然科学版） 2024年第3期39卷 42-49页

作者：闫炎蔡萌马文海张晓川韩礼红刘永红中国石油集团工程材料研究院有限公司陕西西安710077 中国石油集团大庆油田分公司采油工程研究院黑龙江大庆163458 中国石油大学(华东)机电工程学院山东青岛266580

针对盐岩地层普遍出现的套损现象,借助三轴岩石力学实验对取自川东北油气田某地层段盐岩的蠕变特性进行了实验研究。基于实验结果,构建了可描述盐岩的衰减蠕变阶段和稳态蠕变阶段特征的非定常盐岩蠕变模型,基于该盐岩蠕变模型计算深部... 详细信息

针对盐岩地层普遍出现的套损现象,借助三轴岩石力学实验对取自川东北油气田某地层段盐岩的蠕变特性进行了实验研究。基于实验结果,构建了可描述盐岩的衰减蠕变阶段和稳态蠕变阶段特征的非定常盐岩蠕变模型,基于该盐岩蠕变模型计算深部盐岩地层蠕变过程中井筒径向位移的变化,计算结果显示井筒内压能有效地降低盐岩内壁的蠕变位移,而地层水平主应力和上覆地层压力可增大地层的偏差应力,从而增加盐岩内壁的蠕变位移。为避免盐岩蠕变造成套管变形,在水泥中添加空心陶瓷颗粒可有效降低水泥的弹性模量,使得水泥环能充分吸收地层径向蠕变给井筒系统增加的应变能,进而降低对套管的挤压作用,减小套变风险,形成油气井工程上一种新型套管止变技术方法。

关键词：盐岩蠕变套管变形地层滑移水泥环径向位移

胺源对“一锅法”合成聚硼硅氮烷结构及性能的影响

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高分子学报 2024年第2期55卷 161-171页

作者：陈楚童陈艳杰罗永明张宗波徐彩虹中国科学院化学研究所中国科学院极端环境高分子材料重点实验室北京100190 中国科学院大学化学与化工学院北京100049

以六甲基二硅氮烷(MMN)、四甲基二乙烯基二硅氮烷(MMNVi)和四甲基二硅氮烷(MMNH) 3种不同结构的二硅氮烷为胺源,通过与氯硅烷和三氯化硼反应,制备出具有不同封端结构的聚硼硅氮烷.其中,以MMN、MMNVi为胺源可获得液态产物;以MMNH为胺源时... 详细信息

以六甲基二硅氮烷(MMN)、四甲基二乙烯基二硅氮烷(MMNVi)和四甲基二硅氮烷(MMNH) 3种不同结构的二硅氮烷为胺源,通过与氯硅烷和三氯化硼反应,制备出具有不同封端结构的聚硼硅氮烷.其中,以MMN、MMNVi为胺源可获得液态产物;以MMNH为胺源时,因合成过程中发生活性基团间的过度交联导致产物凝胶.采用核磁共振波谱仪、红外光谱仪对液态前驱体聚合物及其热解产物的结构进行了表征.研究结果表明:通过“一锅法”制备的液态聚硼硅氮烷主链具有较多的支化和环状结构,随着封端结构中乙烯基含量的增加,所得前驱体的固化温度降低,固化反应活化能降低.与以MMN为胺源和封端剂合成的聚硼硅氮烷相比,以MMNVi为胺源所得前驱体固化前后陶瓷产率分别提高了14.9%及8.1%.并且,通过改变胺源的种类和比例可以调节热解产物的元素组成,合成的液态前驱体聚合物热解所得SiBCN陶瓷结晶温度高于1700℃.

关键词：前驱体转化法硅硼碳氮陶瓷聚硼硅氮烷 “一锅法”

Underestimation of phosphorus fraction change in the supernatant after phosphorus adsorption onto iron oxides and iron oxide–natural organic matter complexes

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Journal of Environmental sciences 2017年第5期29卷 197-205页

作者： Jinlong yan Tao Jiang Ying Yao Jun Wang Yuanli cai Nelson W.Green Shiqiang wei Chongqing Key Laboratory of Agricultural Resources and Environrnent College of Resources and Environment Department of Environmental Science and Engineering Southwest University Chongcling 400716 China Department of Forest Ecology and Management Swedish University of Agricultural Sciences Umea SE-90183 Sweden School of materials science & engineering Beijing Institute of Technology Beijing 100081 China College of Chemistry and Chemical engineering Mianyang Normal University Mianyang 621000 China School of Chemical and Biomolecular engineering Georgia Institute of Technology Atlanta CA 30332 USA

The phosphorus（P） fraction distribution and formation mechanism in the supernatant after P adsorption onto iron oxides and iron oxide-humic acid（HA） complexes were analyzed using the ultrafiltration method in this *** an initial P concentration of 20 mg/L（I =0.01 mol/L and pH = 7）,it was shown that the colloid（1 kDa-0.45 μm） component of P accounted for 10.6%,11.6%,6.5%,and 4.0%of remaining total P concentration in the supernatant after P adsorption onto ferrihydrite（FH）,goethite（GE）,ferrihydrite-humic acid complex（FH-HA）,goethite-humic acid complex（GE-HA）,*** 〈1 kDa component of P was still the predominant fraction in the supernatant,and underestimated colloidal P accounted for 2.2%,55.1%,45.5%,and 38.7%of P adsorption onto the solid surface of FH,FH-HA,GE and GE-HA,***,the colloid P could not be ***,it could be interpreted that Fe3＋ hydrolysis from the adsorbents followed by the formation of colloidal hydrous ferric oxide aggregates was the main mechanism for the formation of the colloid P in the *** colloidal adsorbent particles co-existing in the supernatant were another important reason for ***,dissolve organic matter dissolved from iron oxide-HA complexes could occupy large adsorption sites of colloidal iron causing less colloid P in the ***,we believe that the findings can provide a new way to deeply interpret the geochemical cycling of P,even when considering other contaminants such as organic pollutants,heavy metal ions,and arsenate at the sediment/soil-water interface in the real environment.

关键词： Phosphorus Fraction Ultrafiltration Natural organic matter Iron-DOM Iron oxide-humic acid complexes

盐度超敏感离子水凝胶的制备及其在可视化盐度检测和智能液体阀上的应用

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science china materials 2024年第1期67卷 321-330页

作者：闫小草师琪蔡玉东佟亚轩吴继红翁云宣高海南 College of Chemistry and materials engineering Beijing Technology and Business UniversityBeijing 100048China Synthetic Resin Laboratory Petrochemical Research InstitutePetrochinaBeijing 102206China

对超低浓度盐溶液响应产生大尺度形变的功能水凝胶在海水渗透能收集、刺激响应分离材料、智能传感和致动器等方面具有广阔的应用前景.本文结合聚电解质和两性离子聚合物开发了一种盐度超敏感离子水凝胶.以稀盐作为分散介质时,水凝胶体... 详细信息

对超低浓度盐溶液响应产生大尺度形变的功能水凝胶在海水渗透能收集、刺激响应分离材料、智能传感和致动器等方面具有广阔的应用前景.本文结合聚电解质和两性离子聚合物开发了一种盐度超敏感离子水凝胶.以稀盐作为分散介质时,水凝胶体积缩小为原来1/60.本文研究了盐响应水凝胶的溶胀、形态和力学性能,并基于拉曼光谱对聚合物网络盐响应重构行为进行了表征.此外,利用毛细管和盐响应水凝胶成功设计了一种可视化、便携离子检测计,可媲美商用水质监测计.同时开发了具有传感和致动功能的智能液阀,用于自动感应调节液体的流出和输送.该盐敏感水凝胶在淡水监测和调控、海水渗透能收集、刺激响应分离材料、智能软机器人和电子穿戴等方面具有很大的应用潜力.

关键词：智能传感聚合物网络水凝胶自动感应机器人分离材料离子检测聚电解质

EFFICIENT WHITE EMITTING COPOLYMERS BASED ON BIPOLAR FLUORENE-co-DIBENZOTHIOPHENE-S,S-DIOXIDE-co-CARBAZOLE BACKBONE

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Chinese Journal of Polymer science 2013年第1期31卷 88-97页

作者： Lei Ying yan-hu Li cai-hong wei Min-quan Wang 杨伟 Hong-bin Wu Yong Cao State Key Laboratory of Luminescent materials and Devices Institute of Polymer Optoelectronic Materials and DevicesSouth China University of Technology School of Material science & engineering South China University of Technology

Efficient white light emitting polymers were synthesized based on poly（9,9-dioctylfluorene-co-dibenzothiophene- S,S-dioxide） as blue emitter and a bisphenylamine functionalized 2,1,3-benzothiadiazole （DPABT） as red emitter. It was found that the incorporation of hole-transporting carbazole moiety into polymer main chain could effectively reduce the hole injection barriers, which can lead to distinctly improved charge balance in the emissive layer. Additionally, the hole- transporting carbazole units may form efficient bipolar host with electron-transporting dibenzothiophene-S,S-dioxide units. The white light emitting diodes based on single polymer PFSOCzDPABT showed the maximum luminous efficiency of 3.3 cd/A with the maximum luminance of 10282 cd/m2, and the luminous efficiency showed only 24% roll off at current density of 400 mA/cm2. These Commission Internationale d＇Enclairage （CIE） coordinates of the devices changed slightly with the driving voltages increasing from 8 V to 12 V, and were very close to National Television System Committee （NTSC） standard white light emission of （0.33, 0.33）. The results indicated that the incorporating bipolar host and low band gap DPABT unit was a promising way to achieve efficient single white light emitting copolymers.

关键词： Fluorene Dibenzothiophene-S,S-dioxide Carbazole White emitting polymer.

Highly Efficient Lattice Boltzmann Model for Compressible Fluids:Two-Dimensional Case

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Communications in Theoretical Physics 2009年第10期52卷 681-693页

作者： CHEN Feng XU Ai-Guo ZHANG Guang-cai GAN yan-Biao cheng Tao LI Ying-Jun china University of Mining and technology （Beijing） Beijing 100083 China National Key Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics P.O. Box 8009-26 Beijing 100088 China North china institute of Aerospace engineering Langfang 065000 China

We present a highly efficient lattice Boltzmann model for simulating compressible flows. This model is based on the combination of an appropriate finite difference scheme, a 16-discrete-velocity model [Kataoka and Tsutahara, Phys. Rev. E 69 （2004） 035701（R）] and reasonable dispersion and dissipation terms. The dispersion term effectively reduces the oscillation at the discontinuity and enhances numerical precision. The dissipation term makes the new model more easily meet with the yon Neumann stability condition. This model works for both high-speed and low-speed flows with arbitrary specific-heat-ratio. With the new model simulation results for the well-known benchmark problems get a high accuracy compared with the analytic or experimental ones. The used benchmark tests include （i） Shock tubes such as the Sod, Lax, Sjogreen, Colella explosion wave, and collision of two strong shocks, （ii） Regular and Mach shock reflections, and （iii） Shock wave reaction on cylindrical bubble problems. With a more realistic equation of state or free-energy functional, the new model has the potential tostudy the complex procedure of shock wave reaction on porous materials.

关键词： lattice Boltzmann method compressible flows specific-heat-ratio von Neumann stability analysis