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Chinese Science Bulletin 2005年第22期50卷 2575-2581页

作者： david g. evans Ministry of Education Key Laboratory of Science and Technolog. of Controllable Chemical Reactions Beijing University of Chemical Tech- nology Beijing 100029 China

A novel org.nic-inorg.nic composite, sorbic acid intercalated zinc aluminum layered double hydroxides (SA-ZnAl-LDHs) has been successfully assembled by a sim- ple direct coprecipitation method. A holistic approach in- cluding.normal XRD, FT-IR, and UV-Vis measurements and simultaneous Tg.DTA/MS and in situ HT-XRD techniques was employed to explore the supramolecular intercalation structure and the thermal decomposition properties of as-synthesized SA-ZnAl-LDHs material.

关键词：氢氧化铝超分子结构热量分解插入结构 HT-XRD 有机化合物

Layer-by-layer assembly of long.afterg.ow self-supporting.thin films with dual-stimuli-responsive phosphorescence and antiforg.ry applications

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Nano Research 2017年第10期10卷 3606-3617页

作者： Rui g.o Dong.eng.Yan david g. evans Xue Duan State Key Laboratory of Chemical Resource Eng.neering Beijing University of Chemical Technology Beijing 100029 China Beijing.Key Laboratory of Energ. Conversion and Storag. Materials College of Chemistry Beijing Normal University Beijing 100875 China

The assembly of thin films （TFs） having.long.lasting.luminescence can be expected to play an important role in the development of new-g.neration smart sensors, anti-counterfeiting.materials, and information-encryption systems. However, such films are limited compared with their powder and solution counterparts. In this study, by exploiting.the self-org.nization of phosphors in the two-dimensional （2D） g.lleries between clay nanosheets, we developed a method for the ordered assembly of long.afterg.ow TFs by utilizing.a hydrog.n-bonding.layer-by-layer （LBL） process. Compared with the pristine powder, the TFs exhibit hig. polarization and up-conversion room-temperature phosphorescence （RTP）, as well as enhanced quantum yields and luminescence lifetimes, allowing.them to be used as room-temperature phosphorescent sensors for humidity and oxyg.n. Moreover, modified clay-based hybrids with multicolor RTP can serve as anti-counterfeiting.marks and triple-mode 2D barcode displays. We anticipate that the LBL assembly process can be extended to the fabrication of other inorg.nic--org.nic room-temperature phosphorescent hybrids with smart luminescent sensor and antiforg.ry applications.

关键词： layer-by-layer self-supporting.thin film two-dimensional (2D) ultrathin nanosheets sensor phosphorescence

Multi-dimensional, lig.t-controlled switch of fluorescence resonance energ. transfer based on orderly assembly of 0D dye@micro-micelles and 2D ultrathin-layered nanosheets

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Nano Research 2016年第12期9卷 3828-3838页

作者： Zhixiong.Li Ruizheng.Liang.Simin Xu Wendi Liu Dong.eng.Yan Min Wei david g. evans Xue Duan State Key Laboratory of Chemical Resource Eng.neering Beijing University of Chemical Technology Beijing 100029 China

Fluorescence resonance energ. transfer （FRET） systems have broad applications in visual detection, intellig.nt materials, and biolog.cal imag.ng. all of which favor the transmission of lig.t throug. multiple dimensions and in diverse directions. Herein, we have demonstrated multi-dimensional （0D and 2D） FRET within a multi-layer ultrathin film （UTF） by employing.a layer-by-layer （LBL） assembly technique. The anionic block copolymer micelle poly（tert-butyl acrylate- co-ethyl acrylate-co-methacrylic acid）（PTBEM） is chosen as a molecular carrier for the incorporation of bis（8-hydroxyquinolate） zinc （Znq2） and open-ring.merocyanine （MC）（denoted as （Znq2/MC）@PTBEM）. Alternatively, electrostatic assembly is performed with cationic layered double hydroxide （LDH） nanosheets （denoted as [（Znq2/MC）@PTBEM/LDH]n）. This [（Znq2/MC）@PTBEM/ LDH]n system offers a multi-dimensional propag.tion medium and ensures that the FRET donor and acceptor are located within their F6rster radii in each direction. The system demonstrates a FRET process that can be switched via alternating.ultraviolet/visible （UV/vis） irradiation, with tunable blue-g.een/red fluorescence, resulting.in a FRET efficiency as hig. as 81.7%. It is expected that this assembly method, which uses 0D micelles on a 2D layered material, can be extended to other systems for further development of multi-dimensional FRET.

关键词： bis(8-hydroxyquinolate)zinc (Znq2) open-ring.merocyanine layered double hydroxide layer-by-layerself-assembly multi-dimensionalfluorescence resonanceenerg. transfer

Layered double hydroxide monolayers for controlled loading.and targ.ted delivery of anticancer drug.

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Nano Research 2018年第1期11卷 195-205页

作者： Xuan Mei Simin Xu Tong.ang.Hu Liuqi Peng.Rui g.o Ruizheng.Liang.Min Wei david g. evans Xue Duan State Key Laboratory of Chemical Resource Eng.neering Beiing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical Technology Beijing 100029 China

Two-dimensional （2D） nanomaterials have g.ined tremendous attention in the field of biomedicine because of their hig. specific surface areas and fascinating.physicochemical properties. Herein, 2D monolayered double hydroxide （MLDH） nanosheets were employed to localize doxorubicin （DOX）, an anticancer drug. with a loading.capacity of as hig. as 3.6 ***-1 （w/w）. Structural characterizations and theoretical calculations indicate that the DOX molecule is uniformly arrang.d and oriented at the surface of the MLDHs with a binding.energ. of 15.90 eV, showing.sig.ificant electrostatic interaction. With the assistance of the targ.ting.ag.nt folic acid （FA）, DOX-FA/MLDHs demonstrate targ.ted cellular uptake and superior anticancer behavior based on in vitro tests performed with cancer cells. In addition, this composite material exhibits a selective release toward cancer cells and g.od biocompatibility with normal cells, which would g.arantee its practical applications in cancer therapy.

关键词： two-dimensional nanomaterials monolayer layered double hydroxide(LDH) drug.loading controllable release

Nanoseparation-lnspired Manipulation of the Synthesis of CdS Nanorods

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Nano Research 2011年第2期4卷 226-232页

作者： Xiaoming.Sun Xiuju Ma Lu Bai Junfeng.Liu Zheng.Chang.david g. evans Xue Duan Jiaou Wang.Joseph F. Chiang State Key Laboratory of Chemical Resource Eng.neering RO. Box 98 Beijing University of Chemical Technology Beijing 100029 China Institute of Hig. Energ. Physics Beijing 100039 China Department of Chemistry and Biochemistry SUNY-Oneonta Oneonta NY 13820 USA

CdS nanorods have been sorted by leng.h using.a density g.adient ultracentrifug. rate separation method. The fractions containing.long.r rods showed relatively strong.r oxyg.n-related surface trap emission, while the shorter ones had dominant band-edg. emission. These results sug.est that the final leng.h distribution of CdS nanorods is not a result of random nucleation and g.owth, but is related to the local synthesis conditions. Inspired by these finding., different synthesis environments (N2, air, and O2) have been employed in order to tailor the leng.h distribution. In addition to the rod leng.h, the photoluminescence properties of CdS nanorods can also be manipulated. Increasing.the oxyg.n partial pressure sig.ificantly chang.d the g.owth behavior of CdS nanorods by improving.the anisotropic g.owth.

关键词： CdS纳米棒合成条件操纵长度分布光致发光特性生长行为分离方法密度梯度

Co^2＋含量对CoAl-LDHs焙烧产物结构、组成及其生长碳纳米管的影响

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无机化学学报 2008年第6期24卷 886-891页

作者： Halidou I.Hima 项顼张璐李峰 david g.evans 北京化工大学化工资源有效利用国家重点实验室北京100029

采用成核晶化隔离法将Co2+引入层状双金属氢氧化物(LDHs),得到了含不同Co2+/Al3+物质的量的比为1∶1,2∶1,3∶1的二元钴铝碳酸根型LDHs(CoAl-LDHs)。通过X射线衍射(XRD)、透射电镜(TEM)、扫描电镜-能量散射谱(SEM-EDS)、拉曼光谱(Raman... 详细信息

采用成核晶化隔离法将Co2+引入层状双金属氢氧化物(LDHs),得到了含不同Co2+/Al3+物质的量的比为1∶1,2∶1,3∶1的二元钴铝碳酸根型LDHs(CoAl-LDHs)。通过X射线衍射(XRD)、透射电镜(TEM)、扫描电镜-能量散射谱(SEM-EDS)、拉曼光谱(Raman)、程序升温还原(TPR)及X射线光电子能谱(XPS)等方法对CoAl-LDHs焙烧产物的结构、组成及其化学气相沉积(CCVD)催化生长多壁碳纳米管(CNTs)进行了研究。结果表明:CoAl-LDHs前体中钴的含量可以明显改变焙烧产物的组成分布和还原性能,并最终影响CNTs的生长,其中以nCo2+/nAl3+比为2/1的LDHs作为催化剂前体可以得到管径均匀和石墨化程度高的CNTs,这与还原得到的纳米活性Co颗粒均匀分散有关。

关键词：层状双金属氢氧化物碳纳米管催化钴

超声浸渍法制备Pd/Al_2O_3催化剂及其催化蒽醌加氢性能

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催化学报 2006年第4期27卷 304-308页

作者：杨永辉林彦军冯俊婷 david g.evans 李殿卿北京化工大学化工资源有效利用国家重点实验室北京100029

以球形-γAl2O3和-θAl2O3为载体,分别采用超声浸渍和普通浸渍方法制备了Pd含量为0.3%的负载型催化剂,并将其用于蒽醌加氢反应.采用X射线衍射、N2吸附和透射电镜等手段对催化剂的理化性质和孔结构进行了分析,考察了浸渍方法对催化剂活... 详细信息

以球形-γAl2O3和-θAl2O3为载体,分别采用超声浸渍和普通浸渍方法制备了Pd含量为0.3%的负载型催化剂,并将其用于蒽醌加氢反应.采用X射线衍射、N2吸附和透射电镜等手段对催化剂的理化性质和孔结构进行了分析,考察了浸渍方法对催化剂活性金属分散度的影响.结果表明,与普通浸渍法相比,超声浸渍法制备的负载型Pd催化剂金属分散度明显提高,因而对蒽醌加氢反应表现出较高的催化活性.以960℃焙烧的球形-θAl2O3为载体,通过超声浸渍制备的负载型Pd催化剂具有较高的Pd分散度和较大的孔径,在蒽醌加氢反应中对反应物的扩散阻力较小,因而表现出更高的催化活性,而且反应中催化剂的稳定性良好.

关键词：超声浸渍蒽醌氢化负载型钯催化剂过氧化氢球形氧化铝

Comparative Study on Luminescence Transformation between the Powder and Film of Dodecylbenzene Included in Carboxymethyl-β-cyclodextrin Functionalized Layered Double Hydroxides

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Comparative Study on Luminescence Transformation between the...

The evolution of lower extremity reconstruction

中国化学会第五届全国结构化学学术会议

作者： Xiaolei Liu Min Wei david g. evans Lan Jin Xue Duan State Key Laboratory of Chemical Resource Eng.neering.Beijing.University of Chemical Technolog.,Beijing.100029,P.R.China

＜正＞Dodecylbenzene（DDB）molecules were incorporated into the cavities of carboxymethyl-β-cyclodextrin which has been intercalated between layers of a Zn/Al layered double hydroxide,throug. two different routes:intercalation-inclusion and inclusion-intercalation, *** film of the resulting.composite was fabricated by the method of solvent

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Plastic and Aesthetic Research 2022年第1期9卷 182-195页

作者： Brog.n g.A.evans david L.Colen Division of Plastic and Reconstructive Surg.ry Department of SurgeryYale School of MedicineNew HavenCT 06510USA

Reconstruction of the lower extremity is a complex task that has evolved g.eatly in both technique and indication over the past *** advances in treating.traumatic lower extremity injuries focused on primary amputation to avoid the hig. mortality of *** introduction of antibiotics improved surg.cal debridement and local reconstructive options,enhancing.the viability of lower extremities with simple and proximal *** the advent of microvascular surg.ry,free tissue transfer techniques provided a means to reconstruct more distal and complex *** these surg.cal techniques have continued to evolve,so too have indications for reconstruction,patient manag.ment and post-operative care-now with a g.eater emphasis on patient quality of life and limb *** purpose of this article is to outline the evolution of lower extremity reconstruction,and how the standard of practice has chang.d over time.

关键词： Lower extremity lower extremity reconstruction limb salvag. free flap perforator flap vascularized bone flap orthoplastic surg.ry

Preparation and photochromic properties of NiAl-NO_3-LDHs/LDPE composite

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Chinese Science Bulletin 2007年第7期52卷 877-882页

作者： CHO Kyuhaeng.david g.evans State Key Laboratory of Chemical Resource Eng.neering Beijing University of Chemical Technology

Nanoscale NiAl-NO3-LDHs with g.od crystallinity have been synthesized by a method, Separate Nucleation and Ag.ng.Steps (SNAS). An NiAl-NO3-LDHs/LDPE composite was prepared by blending.NiAl-NO3-LDHs and LDPE in a heated double-roller mixer. The color of this composite chang.d from olive g.een to steel g.ay under UV irradiation. After heating.at 80oC for 2 h, the color returned to olive g.een. The effect of varying.the amount of added NiAl-NO3-LDHs and UV exposure time on the photochromic properties of the composite has been investig.ted. The results showed that the photochromic phenomenon becomes more apparent with increasing.amount of NiAl-NO3-LDHs. When the amount reaches 5%, the composite exhibits g.od photochromic properties and reproducibility. The color chang. rate of the composite reaches a maximum when the irradiation time exceeds 20 min. The addition of LDPE improves the photochromic cyclability of NiAl-NO3-LDHs sig.ificantly. The addition of nanoscale NiAl-NO3-LDHs also improves the mechanical properties of LDPE to some extent.

关键词： NiAl-NO3-LDHs 低密度聚乙烯纳米级复合物合成对光反应变色结晶度