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Green Energy & Environment 2022年第5期7卷 1033-1044页

作者： Sen Luan Wei Li Zanwu Guo Wenxiu Li xiaojian hou Yi Song Ran Wang Qian Wang Department of Chemistry Capital Normal UniversityBeijing100048China

Well-ordered hierarchically mesoporous/microporous carbon materials have been successfully fabricated by using dual soft-templating approach through compressed CO_(2).Pluronic F127 and different type of surfactants,including nonionic,cationic,and anionic surfactants,were used as dual templates to investigate the influence on the morphology and nanostructure of the as-prepared carbon samples.TEM,SEM,N2 sorption,wide-angle and small-angle XRD analysis were employed to reveal the well-ordered hierarchically micro-mesoporous structure with2 D hexagonal symmetry by using compressed CO_(2).The prepared HPC samples with different pressures as the catalyst carriers have been functioned by chlorosulfonic acid for the fructose conversion into HMF.Chlorosulfonic acid concentration,catalyst dosage and reaction temperature have been optimized for fructose-to-HMF transformation with the obtained catalyst.The performances of as-made HPC-SO_(3) H samples in HMF yield and reaction rate of fructose-to-HMF transformation have been investigated.The stability of the samples was also conducted in the dehydration of fructose to HMF for five cycles.The possible catalytic mechanism by using hierarchically porous carbon materials as catalyst support for fructose-to-HMF transformation was proposed.

关键词： ordered catalyst carbon

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喷水推进船操纵运动数学建模仿真分析

水动力学研究与进展（A辑） 2024年第1期39卷 46-51页

作者：刘小健侯珂吴永顺杨素军喷水推进技术重点实验室上海200011 中国船舶及海洋工程设计研究院上海200011 上海市船舶工程重点实验室上海200011 上海海迅机电工程有限公司上海200011

喷水推进船具有高航速、浅吃水等特点,回转性能优越。该文以喷泵和喷水推进船为研究对象,首先采用称重法,开展喷泵流量标定试验;而后基于裸船体和带四个喷泵的船体,开展水池中约束模平面运动机构模型试验,如斜航运动、横荡运动、摇首运... 详细信息

喷水推进船具有高航速、浅吃水等特点,回转性能优越。该文以喷泵和喷水推进船为研究对象,首先采用称重法,开展喷泵流量标定试验;而后基于裸船体和带四个喷泵的船体,开展水池中约束模平面运动机构模型试验,如斜航运动、横荡运动、摇首运动及自航操舵试验等,获取船体水动力和喷口流量;再采用最小二乘法,回归分析得到相关的水动力导数,建立整体式和分离式操纵运动数学模型,编制喷水推进船的操纵运动程序,数值模拟30°回转运动和10°/10°z形试验,并与外场自由自航模操纵性进行比较。数值模拟结果显示:通过整体式运动数学模型和分离式运动数学方法,战术直径误差在5.5%以内,第一超越角误差为2°左右,这两种方法都能较好地吻合模型试验结果。相较而言,基于整体式运动数学模型的模型试验或CFD数值计算的难度更高且经济成本较大,而在实际工程数值模拟中,基于分离式运动数学模型的数值模拟更容易实施。

关键词：喷水推进操纵整体式运动数学模型分离式运动数学模型

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应对极端风暴潮的粤港澳大湾区海堤建设研究

中国防汛抗旱 2024年第3期34卷 70-75页

作者：侯堋刘晓建朱小伟王强珠江水利委员会珠江水利科学研究院广州510611 水利部珠江河口治理与保护重点实验室广州510611

海堤是防御风暴潮侵袭、减轻海洋灾害的重要工程措施。在海平面上升和风暴潮加剧的双重影响下,大湾区海堤防潮能力被动降低,防潮安全备受挑战。通过现场调查梳理了大湾区海堤典型破坏形式,有防浪墙倾覆、迎水坡损毁及背水坡垮塌等,其中... 详细信息

海堤是防御风暴潮侵袭、减轻海洋灾害的重要工程措施。在海平面上升和风暴潮加剧的双重影响下,大湾区海堤防潮能力被动降低,防潮安全备受挑战。通过现场调查梳理了大湾区海堤典型破坏形式,有防浪墙倾覆、迎水坡损毁及背水坡垮塌等,其中案例中背水坡破坏占比近1/2。为应对极端风暴潮灾害,迫切需要对大湾区海堤进行提标加固,但以提高堤顶高程为主的传统提标方式与城市亲水景观需求矛盾突出,基于此提出大湾区海堤建设应由防浪防潮垂向一体式向防浪防潮横向分离式转变,即利用堤身“挡高潮”,利用堤前措施和堤身“消大浪”。相较于传统提标方法,该方法实现了不抬高堤顶高程却提升防潮能力的目标,成果可为粤港澳大湾区海堤建设提供借鉴。

关键词：粤港澳大湾区风暴潮海堤破坏海堤提标生态海堤

基于人工智能驱动分子工厂技术的Menin抑制剂优化

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中国药科大学学报 2024年第3期55卷 326-334页

作者：曾浩吴国振邹武新王哲宋剑飞施慧汪小涧侯廷军邓亚峰杭州碳硅智慧科技发展有限公司杭州310018 浙江大学药学院杭州310058 中国医学科学院、北京协和医学院药物研究所天然药物活性物质与功能国家重点实验室活性物质发现与适药化研究北京市重点实验室北京100050 清华大学自动化系北京100084

以深度学习为代表的新一代人工智能技术已经成为推动新药研发的重要驱动力。本文创造性地提出了一种基于人工智能技术的创新药物分子设计和优化工作流程“分子工厂”,该流程融合了自主研发的智能分子生成模型、高性能分子对接算法以及... 详细信息

以深度学习为代表的新一代人工智能技术已经成为推动新药研发的重要驱动力。本文创造性地提出了一种基于人工智能技术的创新药物分子设计和优化工作流程“分子工厂”,该流程融合了自主研发的智能分子生成模型、高性能分子对接算法以及高精度亲和力预测方法,已作为核心模块被整合进一站式药物设计软件平台DrugFlow,为先导化合物发现和优化提供了一整套成熟的解决方案。利用“分子工厂”模块,针对Menin蛋白开展了抗耐药第2代抑制剂的研发。通过计算和实验的结合,快速获得多个潜力化合物,其中化合物RG-10对Menin野生型、M327I突变体和T349M突变体的IC50分别为9.681 nmol/L、233.2 nmol/L和40.09 nmol/L;与已进入Ⅱ期临床的阳性参照分子SNDX-5613相比,其对M327I和T349M突变体的抑制活性显著提升。上述研究充分展现了“分子工厂”技术在新药研发项目中的独特优势,能快速高效地针对特定蛋白结构产生高质量的活性分子,对推动新药研发具有重大价值和深远意义。

关键词：分子工厂人工智能分子生成分子对接 Menin抑制剂

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Reliability Analysis of Repairable System with Multiple Closed-Loop Feedbacks Based on GO Method

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Journal of Beijing Institute of Technology 2022年第4期31卷 431-440页

作者： Huina Mu Yuhang Cui Xinrong hou xiaojian Yi Wentao Ma Wei Liu School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China China North Engine Research Institute Tianjing 300400China

In order to solve the problem of reliability modeling and the analysis of complex systems with multiple closed-loop feedbacks,a new reliability analysis method for repairable systems with multiple closed-loop feedbacks is proposed based on the goal-oriented(GO)methodology.Firstly,the basic theories and advantages of GO method are introduced.Secondly,a type-24B multiple closed-loop feedback structure operator is proposed through GO method with its operation formula given,which expands the types of GO method operators and the application scope of their reliability analysis.Finally,taking a certain type of diesel engine fuel supply system an example,the quantitative and qualitative analysis is carried out through GO method,Monte Carlo simulation as well as FTA respectively.The availability results verify the availability of the proposed type-24B operator in the reliability analysis of multiple closed-loop feedback systems.The qualitative analysis results indicate the accuracy and usability of the GO method as a qualitative analysis method.

关键词： multiple closed-loop feedback goal-oriented(GO)method operator reliability analysis

Preparation of Film Based on Polyvinyl Alcohol Modified by Alkaline Starch and Lignin Fiber

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Journal of Renewable Materials 2023年第2期11卷 837-852页

作者： Yunxia Zhou Hisham Essawy Ai Liu Chenyu Yang Defa hou xiaojian Zhou Guanben Du Jun Zhang Yunnan Provincial Key Laboratory of Wood Adhesives and Glued Products Southwest Forestry UniversityKunming650224China Department of Polymers and Pigments National Research CentreDokkiCairo12622Egypt

This study presents an easily prepared film based on alkaline starch-polyvinyl alcohol hybrid and lignin fiber as an additive(SPL film).The SPL film was prepared under acidic conditions through a polycondensation reaction of PVA and a mixture incorporating alkaline starch and lignin fiber from agriculture or forest source.The examination using scanning electron microscopy(SEM)showed that the surface of SPL film was smooth and the lignin fiber had good compatibility within the film hybrid.Electrospray ionization mass spectroscopy(ESI-MS)and fourier transform infrared(FTIR)investigations indicated that alkaline starch and lignin fiber reacted with PVA under acidic conditions and that–CH_(2)–O–groups were involved in the cross-linking of the SPL system.In addition,the SPL film exhibited only 4%light transmittance,which effectively reduces the ultraviolet and visible light(UV-Vis)penetration,along with good performance when exposed to thermal degradation,in which the mass loss reached around 60%at 400℃.More-over,the SPL film acquired excellent tensile strength,which is much higher than that of PVA-lignin(PL)composite film.

关键词： Bio-based film starch lignin fiber polyvinyl alcohol tensile strength

Experimental study on flocculation and sedimentation characteristics of cohesive fine sediment measured using ultrasound in the Pearl River Estuary

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International Journal of Sediment Research 2023年第6期38卷 880-890页

作者： Qinqin Liu xiaojian Liu Jian Chen Peng hou Yong He Qisong Wang Xiaowei Zhu Qiang Wang Huan Gao Pearl River Hydraulic Research Institute Pearl River Water Resources Commission of the Ministry of Water Resources Key Laboratory of the Pearl River Estuary Regulation and Protection of the Ministry of Water Resources School of Water Conservancy North China University of Water Resources and Electric Power Department of the College of Water Conservancy and Hydropower Engineering Hohai University

Flocculation-settling of cohesive fine sediment is the main cause of sediment deposition and changes in topography and geomorphology in estuaries.However,studies on estuary morphology have often focused on a single influencing factor,and sediment deposition characteristics under disturbances in sediment concentration,moisture content,and external forces have rarely been considered simultaneously.The authors propose an ultrasound-assisted flocculation-settling method to analyze the various factor affecting cohesive sediment.The current study examined the sedimentation patterns of cohesive sediment with a sediment content concentration of 30%-80% through ultrasound experiments.The results show that when the sediment concentration is 40%-50%,the best effect on flocculation and sedimentation is induced by ultrasound waves.The corresponding settling height at the clear-muddy water interface is 3.05-3.45 cm,and the settling rate is 0.161-0.173 cm/min.Finally,using ultrasound waves,a moisture content of the sediment concentration of 30%-80% was analyzed based on wet and dry conditions.Taking a sediment concentration of 50% as an example,the maximum values of the variation in the water contents of the upper,middle,and lower layers of the wet basis were 0.82%,0.51%,and0.37%,respectively,whereas those of the upper,middle,and lower layers of the dry basis were 4.77%,1.07%,and 0.60%,respectively.Thus,the moisture content of dry and wet sediment varied as follows:Wupper> Wmiddle> Wlower.The current research results can provide a theoretical basis and technical reference for siltation in channels,harbors,and reservoirs;the evolution of submarine deltas and coastal beaches;transportation of fluid mud;and the treatment of hyper-concentrated sediment flows.

关键词： Cohesive sediment Flocculation-settling Moisture content Ultrasound experiments

复方土槿皮酊与外用液体药用高密度聚乙烯瓶相容性研究

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中国药业 2024年第11期33卷 48-52页

作者：苏锐辉江涛李高捷陈晓坚曾晨侯艳冬汤迎湛广州白云山敬修堂药业股份有限公司广东广州510130

目的探讨复方土槿皮酊与外用液体药用高密度聚乙烯瓶的相容性。方法采用高效液相色谱法测定苯甲酸和水杨酸的含量,按2020年版《中国药典(四部)》通则0711第一法(毛细管柱法)测定乙醇体积分数。依据《药品包装材料与药物相容性试验指... 详细信息

目的探讨复方土槿皮酊与外用液体药用高密度聚乙烯瓶的相容性。方法采用高效液相色谱法测定苯甲酸和水杨酸的含量,按2020年版《中国药典(四部)》通则0711第一法(毛细管柱法)测定乙醇体积分数。依据《药品包装材料与药物相容性试验指导原则》,通过加速试验[温度(40±2)℃、相对湿度(90±10)%条件下放置6个月],长期试验[温度(25±2)℃、相对湿度(60±10)%条件下放置12个月],加严条件的影响因素试验条件下[温度(25±2)℃、相对湿度(20±5)%(低湿)和温度(25±2)℃、相对湿度(90±10)%(高湿)条件下分别放置6个月],以及多次开启试验,考察高密度聚乙烯瓶包装的复方土槿皮酊实际使用过程中苯甲酸、水杨酸含量及乙醇体积分数的变化。结果苯甲酸和水杨酸的进样量分别在0.102~1.812μg和0.050~0.906μg范围内与峰面积线性关系良好(R~2=0.999 9,n=5);精密度、稳定性、重复性试验结果的RSD均小于0.5%(n=6);平均加样回收率分别为99.34%和99.24%,RSD分别为0.72%和0.92%(n=6)。加速试验、长期试验及加严条件的影响因素试验(低湿和高湿)条件下,3批样品均为黄棕色至红棕色的澄清溶液,无沉淀、浑浊、变色,无微粒、块状物析出。在加速试验中,3批样品中苯甲酸和水杨酸平均含量及乙醇平均体积分数分别为120.95~121.27 mg/mL、60.30~61.45 mg/mL、78.49%~79.49%,RSD均小于2.0%(n=18);在长期试验中,分别为121.06~121.89 mg/mL、60.49~61.81 mg/mL、79.40%~79.70%,RSD均小于2.0%(n=18);在低湿加严条件的影响因素试验中,分别为121.64~122.89 mg/mL、60.55~61.88 mg/mL、79.23%~80.05%,RSD均小于2.0%(n=18);在高湿加严条件的影响因素试验中,分别为121.11~122.99 mg/mL、60.51~61.88 mg/mL、79.45%~80.41%,RSD均小于2.0%(n=18)。多次开启试验结果显示,3批样品中苯甲酸和水杨酸平均含量及乙醇平均体积分数分别为121.86~123.90 mg/mL、60.60~62.08 mg/mL、79.74%~80.57%,RSD均小于2.0%(n=9)。结论所建立的高效液相色谱法结果准确、精密度和重复性均良好,可用于复方土槿皮酊中苯甲酸和水杨酸的含量测定。外用液体药用高密度聚乙烯瓶与复方土槿皮酊的相容性良好,可保证复方土槿皮酊的质量稳定。

关键词：复方土槿皮酊高密度聚乙烯瓶相容性苯甲酸水杨酸乙醇

SYMPLECTIC ANALYSIS FOR WAVE PROPAGATION OF HIERARCHICAL HONEYCOMB STRUCTURES

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Acta Mechanica Solida Sinica 2015年第3期28卷 294-304页

作者： Kai Zhang Zichen Deng xiaojian Xu Xiuhui hou Junmiao Meng School of Mechanics Civil Engineering and Architecture Northwestern Polytechnical University School of Civil Engineering Chang'an University

Wave propagation in two-dimensional hierarchical honeycomb structures with two- order hierarchy is investigated by using the symplectic algorithm. By applying the variational prin- ciple to the dual variables, the wave propagation problem is transformed into a two-dimensional symplectie eigenvalue problem. The band gaps and spatial filtering phenomena are examined to find the stop bands and directional stop bands. Special attention is directed to the effects of the relative density and the length ratio on the band gaps and phase constant surfaces. This work provides new opportunities for designing hierarchical honeycomb structures in sound insulation applications.

关键词： hierarchical honeycomb structures wave propagation band gap phase constant surface symplectic analysis

Solution for polarimetric radar cross section measurement and calibration

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Journal of Systems Engineering and Electronics 2014年第2期25卷 211-216页

作者： Peikang Huang Chao Ning xiaojian Xu Hua Yan Zhaoguo hou Science and Technology on Electromagnetic Scattering Laboratory School of Electronic and Information Engineering Beihang University

The exact radar cross-section （RCS） measurement is difficult when the scattering of targets is low. Ful polarimetric cali-bration is one technique that offers the potential for improving the accuracy of RCS measurements. There are numerous polarimetric calibration algorithms. Some complex expressions in these algo-rithms cannot be easily used in an engineering practice. A radar polarimetric coefficients matrix （RPCM） with a simpler expression is presented for the monostatic radar polarization scattering matrix （PSM） measurement. Using a rhombic dihedral corner reflector and a metal ic sphere, the RPCM can be obtained by solving a set of equations, which can be used to find the true PSM for any target. An example for the PSM of a metal ic dish shows that the proposed method obviously improves the accuracy of cross-polarized RCS measurements.

关键词： radar cross section （RCS） polarization scattering ma-trix （PSM） polarimetric calibration polarimetry.