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Enzyme‐like mechanism of selective toluene oxidation to benzaldehyde over organophosphoric acid‐bonded nano‐oxides

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Chinese Journal of Catalysis 2021年第9期42卷 1509-1518页

作者： changshun deng Yun Cui Junchao Chen Teng Chen Xuefeng Guo Weijie Ji Luming Peng Weiping Ding Key Laboratory of Mesoscopic Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023JiangsuChina

The completely selective oxidation of toluene to benzaldehyde with dioxygen,without the need touse H_(2)O_(2),halogens,or any radical initiators,is a reaction long desired but never previously ***,we demonstrate the enzyme‐like mechanism of the reaction over hexadecylphosphateacid(HDPA)‐bonded nano‐oxides,which appear to interact with toluene through specific *** active sites of the catalyst are related to the ability of HDPA to change its bonding to theoxides between monodentate and bidentate during the reaction *** greatly enhances themobility of the crystal oxygen or the reactivity of the catalyst,specifically in toluene *** catalytic cycle of the catalyst is similar to that of methane *** thepresence of catalyst and through O_(2)oxidation,the conversion of toluene to benzaldehyde is initiatedat 70°*** envision that this novel mechanism reveals alternatives for an attractive route to designhigh‐performance catalysts with bioinspired structures.

关键词： Selective oxidation Toluene Benzaldehyde Hexadecylphosphate acid Enzyme‐like Mechanism

Exclusively catalytic oxidation of toluene to benzaldehyde in an O/W emulsion stabilized by hexadecylphosphate acid terminated mixed-oxide nanoparticles

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Chinese Journal of Catalysis 2020年第2期41卷 341-349页

作者： changshun deng Mengxia Xu Zhen Dong Lei Li Jinyue Yang Xuefeng Guo Luming Peng Nianhua Xue Yan Zhu Weiping Ding Key Laboratory of Mesoscopic Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093JiangsuChina Luoyang R&D Center of Technology Sinopec Engineering(Group)Co.Ltd.Luoyang 471003HenanChina

A series of hexadecylphosphate acid(HDPA) terminated mixed-oxide nanoparticles have been investigated to catalyze the oxidation of toluene exclusive to benzaldehyde under mild conditions in an emulsion of toluene/water with the catalysts as stabilizers. With the HDPA-Fe2 O3/Al2 O3 as the basic catalyst, a series of transition metals, such as Mn, Co, Ni, Cu, Cr, Mo, V, and Ti, was respectively doped to the basic catalyst to modify the performance of the catalytic system, in expectation of influencing the mobility of the lattice oxygen species in the oxide catalysts. Under normally working conditions of the catalytic system, the nanoparticles of catalysts located themselves at the interface between the oil and water phases, constituting the Pickering emulsion. Both the doped iron oxide and its surface adsorbed hexadecylphosphate molecules were essential to the catalytic system for excellent performances with high toluene conversions as well as the exclusive selectivity to benzaldehyde. Under optimal conditions, ~83% of toluene conversion and >99% selectivity to benzaldehyde were obtained, using molecular oxygen as oxidant and HDPA-(Fe2 O3-Ni O)/Al2 O3 as the catalyst. This process is green and low cost to produce high quality benzaldehyde from O2 oxidation of toluene.

关键词： Toluene oxidation Benzaldehyde Hexadecylphosphate acid Molecular oxygen Pickering

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主从同步晶振频率误差的卡尔曼收敛算法

探测与控制学报 2022年第2期44卷 41-47页

作者：邓长顺牛兰杰黄辉西安机电信息技术研究所陕西西安710065

针对无线平台时间控制高精度要求,而现有算法忽略了无线信道数据包冲突导致硬件物理时钟延迟抖动及时间戳的采集等噪声影响精度,提出主从同步晶振频率误差的卡尔曼收敛算法。该算法通过建立无线组网主从同步节点时钟硬件物理模型,分析... 详细信息

针对无线平台时间控制高精度要求,而现有算法忽略了无线信道数据包冲突导致硬件物理时钟延迟抖动及时间戳的采集等噪声影响精度,提出主从同步晶振频率误差的卡尔曼收敛算法。该算法通过建立无线组网主从同步节点时钟硬件物理模型,分析晶振频率偏差与高斯白噪声对于算法的有效性、可靠性影响。仿真实验验证结果表明,经过卡尔曼滤波时间估计控制后,有限同步次数下,时间同步精度可从百微秒量级提升至十微秒以内,同步精度方差稳定在1以内,有效降低了晶振频率偏差对时间同步精度的影响。

关键词：晶振频率误差卡尔曼滤波主从同步时间同步精度

基于重组E2蛋白的牛病毒性腹泻病毒间接ELISA抗体检测方法的建立与评价

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中国畜牧兽医 2024年第12期51卷 5459-5469页

作者：张宜宸孙明军邓昌顺丁家波徐宝梁陈磊全春兰赵康范学政秦彤中国农业科学院北京畜牧兽医研究所北京100193 中国动物卫生与流行病学中心青岛266033 翔创科技有限公司北京102600 天津嘉立荷牧业集团有限公司天津300450

【目的】通过真核系统表达牛病毒性腹泻病毒(Bovine viral diarrhea virus,BVDV)E2蛋白,以此为包被蛋白建立一种BVDV间接ELISA抗体检测方法,以解决中国BVDV抗体检测技术不足的问题。【方法】将BVDV E 2基因克隆至真核表达载体pTT5,转染2... 详细信息

【目的】通过真核系统表达牛病毒性腹泻病毒(Bovine viral diarrhea virus,BVDV)E2蛋白,以此为包被蛋白建立一种BVDV间接ELISA抗体检测方法,以解决中国BVDV抗体检测技术不足的问题。【方法】将BVDV E 2基因克隆至真核表达载体pTT5,转染293F细胞,待50%细胞死亡后进行超声破碎,并使用Ni离子亲和层析的方法纯化重组E2(rE2)蛋白;以rE2蛋白作为包被抗原,通过对各反应条件进行优化后建立检测BVDV抗体的间接ELISA方法,进行敏感性、特异性、重复性评价,并与中和试验进行比对。用所建方法对不同省份的牛血清样本进行检测。【结果】采用293F细胞表达了rE2蛋白,经亲和层析方法纯化,rE2蛋白的纯度为99%,浓度为1.74 mg/mL;通过对各个反应条件优化,成功建立了BVDV间接ELISA抗体检测方法。该方法与商品化试剂盒的灵敏度一致,均可检出抗体效价临界血清(VN=1);具有良好的特异性,与传染性牛鼻气管炎病毒(IBRV)、牛副流感病毒-3(BPIV-3)、牛呼吸道合胞病毒(BRSV)和牛疱疹病毒-1(BHV-1)抗体阳性血清均无交叉反应;板内和板间重复性试验的变异系数均在5%以内,证明该方法重复性较好;与血清中和试验的符合率为97.5%。临床样本检测结果显示,共检测出364份阳性血清和64份阴性血清。【结论】基于真核表达的rE2蛋白所建立的BVDV间接ELISA抗体检测方法具有良好的特异性和敏感性,可用于BVDV抗体检测,本研究结果为中国牛病毒性腹泻防控工作提供一种有效的技术手段。

关键词：牛病毒性腹泻病毒(BVDV) E2蛋白间接ELISA

Adaptive Multi-Bernoulli Filter Without Need of Prior Birth Multi-Bernoulli Random Finite Set

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Chinese Journal of Electronics 2018年第1期27卷 115-122页

作者： YUAN changshun WANG Jun LEI Peng SUN Jinping School of Electronic and Information Engineering Beihang University

Conventional Multi-Bernoulli(MBer) filter assumes that the birth MBer Random finite set(RFS)is known a priori. However, this is not true for practical scenario. This paper proposes a novel extension of the MBer filter which eliminates the reliance of the prior birth MBer RFS and relaxes the limitation in new-born target appearance volume. The proposed filter classifies the measurements into survival measurements and birth measurements, and adaptively generates the birth MBer RFS using the birth measurements. The novel filtering equations that distinguish the persistent and new-born targets are derived. A Sequential Monte-Carlo(SMC) implementation of the proposed filter is given. Simulations are performed to verify the improvement in the performance of the proposed filter.

关键词： Random finite set Adaptive multi-Bernoulli filter Sequential Monte-Carlo Multi-target tracking

Numerical and experimental investigation into the evolution of the shock wave when a muzzle jet impacts a constrained moving body

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Defence Technology（防务技术） 2024年第3期33卷 317-326页

作者： Zijie Li Hao Wang changshun Chen Kun Jiang School of Energy and Power Engineering Nanjing University of Science and TechnologyNanjing 210016China

The gun-track launch system is a new special launch device that connects the track outside the *** it is constrained by the track,the characteristics of development of the muzzle jet differ from those of the traditional muzzle ***,it changes from freely developing to doing so in a constrained manner,where this results in an asymmetric direction of flow as well as spatio-temporal coupling-induced interference between various shock waves and the formation of *** this background,the authors of this article formulate and consider the development and characteristics of evolution of the muzzle jet as it impacts a constrained moving *** designed simulations to test the gun-track launch system,and established a numerical model based on the dynamic grid method to explore the development and characteristics of propagation of disturbances when the muzzle jet impacted a constrained moving *** also considered models without a constrained track for the sake of *** results showed that the muzzle jet assumed a circumferential asymmetric shape,and tended to develop in the area above the *** the test platform was close to the ground,the muzzle jet was subjected to reflections from it that enhanced the development and evolution of various forms of shock waves and vortices in the muzzle jet to exacerbate its rate of distortion and asymmetric *** in turn led to significant differences in the changes in pressure at symmetric points that would otherwise have been *** results of a comparative analysis showed that the constrained track could hinder the influence of reflections from the ground on the muzzle jet to some extent,and could reduce the velocity of the shock waves inducing the motion of the muzzle as well as the Mach number of the moving *** work here provides a theoretical basis and the requisite technical support for applications of the gun-track launch *** also sheds light on the

关键词： Shock wave/vortex interference Muzzle jet Constrained boundary Dynamic grid

Immunomodulatory properties of mesenchymal stem cells/dental stem cells and their therapeutic applications

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Cellular & Molecular Immunology 2023年第6期20卷 558-569页

作者： Peishan Li Qianmin Ou Songtao Shi changshun Shao The First Afliated Hospital of Soochow University State Key Laboratory of Radiation Medicine and ProtectionInstitutes for Translational MedicineSoochow UniversitySuzhou PR China South China Center of Craniofacial Stem Cell Research Hospital of StomatologyGuangdong Provincial Key Laboratory of StomatologySun Yat-Sen UniversityGuangzhouPR China

Mesenchymal stem/stromal cells(MsCs)are widely distributed in the body and play essential roles in tissue regeneration and *** can be isolated from discarded tissues,expanded in vitro and used as therapeutics for autoimmune diseases and other chronic *** promote tissue regeneration and homeostasis by primarily acting on immune *** least six different types of MsCs have been isolated from postnatal dental tissues and have remarkable immunomodulatory *** stem cells(DsCs)have been demonstrated to have therapeutic effects on several systemic inflammatory ***,MsCs derived from nondental tissues such as the umbilical cord exhibit great benefits in the management of periodontitis in preclinical ***,we discuss the main therapeutic uses of MSCs/DSCs,their mechanisms,extrinsic inflammatory cues and the intrinsic metabolic circuitries that govern the immunomodulatory functions of MSCs/*** understanding of the mechanisms underpinning the immunomodulatory functions of MSCs/DSCs is expected to aid in the development of more potent and precise MSC/DSC-based therapeutics.

关键词： Mesenchymal stem cells Dental stem cells Immunoregulation Inflammation

Bioinspired mineralized collagen scaffolds for bone tissue engineering

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Bioactive Materials 2021年第5期6卷 1491-1511页

作者： Zhengwei Li Tianming Du changshun Ruan Xufeng Niu Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education School of Biological Science and Medical EngineeringBeihang UniversityBeijing100083PR China Research Center for Human Tissue and Organs Degeneration Institute of Biomedicine and BiotechnologyShenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen518055PR China Beijing Advanced Innovation Center for Biomedical Engineering Beihang UniversityBeijing100083PR China Research Institute of Beihang University in Shenzhen Shenzhen518057PR China

Successful regeneration of large segmental bone defects remains a major challenge in clinical orthopedics,thus it is of important significance to fabricate a suitable alternative material to stimulate bone *** to their excellent biocompatibility,sufficient mechanical strength,and similar structure and composition of natural bone,the mineralized collagen scaffolds(MCSs)have been increasingly used as bone substitutes via tissue engineering ***,we thoroughly summarize the state of the art of MCSs as tissue-engineered scaffolds for acceleration of bone repair,including their fabrication methods,critical factors for osteogenesis regulation,current opportunities and challenges in the ***,the current fabrication methods for MCSs,mainly including direct mineral composite,in-situ mineralization and 3D printing techniques,have been proposed to improve their biomimetic physical structures in this ***,three aspects of physical(mechanics and morphology),biological(cells and growth factors)and chemical(composition and cross-linking)cues are described as the critical factors for regulating the osteogenic feature of ***,the opportunities and challenges associated with MCSs as bone tissue-engineered scaffolds are also discussed to point out the future directions for building the next generation of MCSs that should be endowed with satisfactorily mimetic structures and appropriately biological characters for bone regeneration.

关键词： Collagen Mineralization Scaffold Bone repair 3D printing Biomechanics

Two-Layer Information Granulation:Mapping-Equivalence Neighborhood Rough Set and Its Attribute Reduction

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Intelligent Automation & Soft Computing 2023年第8期37卷 2059-2075页

作者： changshun Liu Yan Liu Jingjing Song Taihua Xu School of Computer Jiangsu University of Science and TechnologyZhenjiang212100China Key Laboratory of Oceanographic Big Data Mining&Application of Zhejiang Province Zhejiang Ocean UniversityZhoushan316022China

Attribute reduction,as one of the essential applications of the rough set,has attracted extensive attention from *** granulation is a key step of attribute reduction,and its efficiency has a significant impact on the overall efficiency of attribute *** information granulation of the existing neighborhood rough set models is usually a single layer,and the construction of each information granule needs to search all the samples in the universe,which is *** fill such gap,a new neighborhood rough set model is proposed,which aims to improve the efficiency of attribute reduction by means of two-layer information *** first layer of information granulation constructs a mapping-equivalence relation that divides the universe into multiple mutually independent mapping-equivalence *** second layer of information granulation views each mapping-equivalence class as a sub-universe and then performs neighborhood informa-tion granulation.A model named mapping-equivalence neighborhood rough set model is derived from the strategy of two-layer information *** results show that compared with other neighborhood rough set models,this model can effectively improve the efficiency of attribute reduction and reduce the uncertainty of the *** strategy provides a new thinking for the exploration of neighborhood rough set models and the study of attribute reduction acceleration problems.

关键词： Attribute reduction information granulation mapping-equiva-lence relation neighborhood rough set