Deep oxidative desulfurization of gas oil based on sandwich-type polysilicotungstate supported β-cyclodextrin composite as an efficient heterogeneous catalyst

In this work,in order to obtain deep clean gas oil,a novel organic–inorganic hybrid(n-C4H9)4N)7H5Si2W18Cd4O68@β-cyclodextrin(abbreviated as TBA-Si WCd@β-CD)composite was synthesized by supporting quaternary ammonium salt of sandwich-type polysilicotungstate onβ-cyclodextrin(TBA-SiWCd@β-CD)as an efficient catalyst for oxidative desulfurization(ODS)of gas oil.The successful composition of the materials explained by the formation of host–guest inclusion complex,which confirmed through FTIR,UV–vis,XRD,SEM,and EDX characterization analyses.Experimental results revealed that the levels of sulfur content and mercaptan compounds of gas oil lowered with 97%removal efficiency.Compared with the ODS treatment of gas oil,the TBA-Si WCd@β-CD composite showed an outstanding catalytic performance for the oxidation of dibenzothiophene(DBT)in the prepared model fuel.The main factors that influence the desulfurization efficiency and the kinetic study of the ODS process were investigated.The prepared heterogeneous catalyst was found to give remarkable reusability for five runs without a discernible decrease in its activity.This study suggested the potential application of the TBA-Si WCd@β-CD catalyst for removal of hazardous sulfur compounds from gas oil fuel.

An Organic-inorganic Hybrid Sandwich-type Arsenotungstate [H_2dap]_2H_2[Ni(dap)_2][Ni(dap)_2(H_2O)_2]- [Ni_4(H_2O)_2(B-α-As^VW_9O_(34))_2]·8H_2O

A new organic-inorganic hybrid sandwich-type arsenotungstate[H2dap]2H2[Ni（dap）2] [Ni（dap）2（H2O）2][Ni4（H2O）2（B-α-AsVW9O34）2]·8H2O 1 （dap = 1,2-diaminopropane） has been synthesized by the reaction of Na6[AsIII2W21O69（H2O）]·nH2O, NiCl2·6H2O and dap under hydrothermal conditions and structurally characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis and single-crystal X-ray diffraction. 1 crystallizes in the monoclinic space group P21/n with a = 13.5133（19）, b = 19.043（3）, c = 17.647（2）, β = 102.585（2）°, V = 4432.0（11） 3, T = 296（2） K, Z = 2, μ = 25.350 mm–1, GOOF = 1.058, R = 0.0353 and wR = 0.0838. The molecular unit of 1 consists of two diprotonated [H2dap]2＋ cations, two protons, one four-coordinate [Ni（dap）2]2＋ cation, one six-coordinate [Ni（dap）2（H2O）2]2＋ cation, one classic tetra-NiII substituted sandwich-type [Ni4（H2O）2（B-α-AsVW9O34）2]10– polyoxoanion and eight lattice water molecules. Furthermore, some reported different types of transition-metal substituted sandwich-type polyoxoanions are summarized and compared.

Synthesis and Crystal Structure of an Infinite Sandwich-type Cu(I) Coordination Polymer: {[Cu(abpy)_2](H_3bptc)·(H_2O)}_n Constructed by a Tetracarboxylic Acid

The title compound {[Cu（abpy）2]（H3bptc）·（H2O）}n, an ion-pair complex of [Cu（abpy）2]＋ with [（H3bptc）]- （abpy = 3,3＇-dimethyl-2,2＇-bipyridine and H4bptc = 1,1＇-biphenyl-2,2＇,3,3＇-tetracarboxylic acid）, has been synthesized by a hydrothermal reaction, and its structure was deter- mined by X-ray diffraction and characterized by elemental analysis and IR spectrum. The crystal is of triclinic, space group P1 with a = 8.4955（12）, b = 15.164（2）, c = 15.303（2）, α = 105.704（3）, β = 97.374（3）, γ = 96.764（3）o, CuC40H35N4O9, Mr = 779.26, V = 1857.9（4）3, Dc = 1.393 g/cm3, F（000） = 808, μ = 0.649 mm-1, S = 1.026 and Z = 2. The final R = 0.0493 and wR = 0.1034 for 4026 observed reflections with I 2σ（I）. The copper（I） coordination polymer demonstrates a 3-D sandwich-type structure containing 2-D double H3bptc-chain layers intercalated with the [Cu（abpy）2]＋ layers by extensive hydrogen bonding interactions.

SANDWICH-TYPE THEOREMS FOR MEROMORPHIC MULTIVALENT FUNCTIONS ASSOCIATED WITH THE LIU-SRIVASTAVA OPERATOR

The purpose of this article is to obtain some subordination and superordi- nation preserving properties of meromorphic multivalent functions in the punctured open unit disk associated with the Liu-Srivastava operator. The sandwich-type results for these meromorphic multivalent functions are also considered.

Poly(N-isopropylacrylamide)-based Vertically Sandwich-typed Hydrogel with Fast Temperature-response Speed and Its Controlled-release Characteristics

A novel poly（N-isopropylacrylamide）-based sandwich-typed hydrogel, which was featured with both ends of linear poly（N-isopropylaerylamide） （PNIPAM） chains being grafted onto cross-linked PNIPAM chains, was successfully prepared in a three-step process by a method of sequential synthesis. The proposed hydrogel displays faster and hydration/dehydration dynamic response to temperature cycling owing to linear PNIPAM chains to form big-pore structure. This work may lead to high attraction for targeting drug delivery systems, polymeric pump, sensors and so on.

Hydrothermal Synthesis and Crystal Structure of a New Sandwich-type Molybdenum Phosphate

The crystal structure of the title compound, [enH2][Fe{MoⅤ6O12(OH)3(HPO4)- (H2PO4)3}2]6en6H2O (en = H2NCH2CH2NH2), hydrothermally synthesized from a mixture of Na2MoO42H2O, Fe2(SO4)3, H3PO4, H2N(CH2)2NH2 and water, has been determined by single- crystal X-ray diffraction. The crystal is of triclinic, space group P?with a = 11.9014(1), b = 13.4246(2), c = 13.8719(2) , a = 87.465(1), b = 69.981(1), g = 64.960(1)? V = 1873.46(4) 3, Z = 1, Mr = 2997.89, F(000) = 1466, m = 2.427 mm-1 and Dc = 2.657 g/cm3. The final R = 0.0404 for 5570 observed reflections (I > 2s(I)). The structural analysis reveals that each cluster anion contains two coplanar {Mo6} rings of six edge-sharing Mo(O5OH) octahedra, and the two {Mo6} rings are linked together through one octahedral FeⅡ ion to generate a sandwich-type cluster with rigorous () symmetry. Moreover, these clusters are further linked into a three-dimensional frame- work by hydrogen bonds.

Laterally Sandwich-typed Hydrogel Columns with Liner Poly(N-isopropylacrylamide) Layer:Preparation, Swelling/deswelling Kinetics and Drug Delivery Characteristics

A novel thermo-responsive hydrogel column, featured with both ends of linear poly（N- isopropylacrylarnide） （PNIPAM） chains being grafted onto cross-linked PNIPAM chains, was reported. The laterally sandwich-typed hydrogel columns were fabricated by radical polymerization in a three-step process using a method of ice-melting synthesis. The initiating path, morphology and thermoresponsive characteristics of the prepared hydrogel columns were experimentally studied. The results show that the hydrogel column obtained by the initiator inside part has more quick swelling and deswelling rates responsing to temperature cycling than other hydrogels owing to linear PNIPAM chains to form supermacroporous structure. The proposed hydrogel structure provide a new mode of the phase transition behavior for thermo-sensitive ＂smart＂ or ＂intelligent＂ monodisperse micro-actuators, which is highly attractive for targeting drug delivery systems, chemical separations, and sensors and so on.

A New Sandwiched-type Polyoxotungstate Containing {Cd_4} Transition-metal Cluster:Synthesis,Structure and Luminescent Property

A new sandwiched polyoxometalate [HK11Cd4Cl2（PW9034）2]·18H2O （1）, incor- porating a unique hybrid tetranuclear cadmium cluster （abbreviated to {Cd4}） with two trivacant polyanions [B-α-PW9O34]9-, has been hydrothermally synthesized and structurally characterized by elemental analyses, IR spectroscopy, UV-vis, and single-crystal X-ray diffraction analysis. Crystal data for 1： monoclinic, space group C2/c, a = 19.2997（4）, b = 13.8014（3）, c = 31.9819（8） A, β = 102.764（2）°, V= 8308.3（3） A3, Z = 4, P2O86Cl2K11Cd4W18H37, Mr = 5735.13, Dc = 4.584 mg-mm-3, F（000） = 10084, μ = 26.579 mm-1, the final R = 0.0378 and wR = 0.0989 for 6558 observed reflections （I〉 2σ（I））. X-ray crystallographic study shows that the molecular structure of 1 contains four cadmium atoms. Two CdO6 distorted octahedra and two CdOsC1 distorted octahedra combine with each other in turn via edge-sharing, resulting in a regular rhomb-like cluster sandwiched between two {B-a-PW9034} units. Further, the sandwich-type polyoxoanions were connected by K＋ ions to form a complicated 3-D open-framework through connecting with each terminal O atom of the [Cd4C12（PW9O34）2]12- polyoxoanions. In addition, compound 1 exhibits photoluminescence property at room temperature and the band gap can be assessed at 3.25 eV.

UNCONVENTIONAL HAMILTON-TYPE VARIATIONAL PRINCIPLES FOR DYNAMICS OF REISSNER SANDWICH PLATE

According to the basic idea of classical yin-yang complementarity and modern dual-complementarity, in a simple and unified way proposed by Luo（1987）, some uncon ventional Hamilton-type variational principles for dynamics of Reissner sandwich plate can be established systematically. The unconventional Hamilton-type variation principle can fully characterize the initial boundary value problem of this dynamics. In this paper, an important integral relation is given, which can be considered as the generalized principle of virtual work in mechanics. Based on this relation, it is possible not only to obtain the principle of virtual work in dynamics of Reissner sandwich plate, but also to derive systematically the complementary functionals for fivefield, two-field and one-field unconventional Hamilton-type variational principles by the generalized Legender transformations. Furthermore, with this approach, the intrinsic relationship among the various principles can be explained clearly.

面内驱动旋转超声电机的研究进展

超声电机利用压电陶瓷的逆压电效应和机械共振来获得其运动和力矩,具有响应快速、定位精度好、可直接驱动等诸多优点,在精密驱动、航空航天、生物医学等领域具有独特的应用优势和成功应用,已有成熟产品实现产业化。基于面内振动模态的微小型超声电机是目前相关研究最易于微小型化的一类,在微机电系统领域具有很好的应用潜力和空间。首先,介绍了超声电机的工作原理;其次,针对夹心式换能器定子结构和贴片式定子结构两种类型面内驱动旋转超声电机,从不同的结构形式、输出性能、应用研究方面归纳总结相关研究的新进展和新成果,比较分析了几种电机样机的主要性能;最后,指出需要深入研究和技术突破的几个问题。

船用C型夹层板隔声性能研究

夹层板作为一种新型结构,具有设计性强、重量轻、比刚度高、减振隔声性能好等优点,已被应用于各种工程结构。然而,其夹层结构形式种类繁多,对复杂夹层结构的隔声性能进行理论分析比较困难,亟需开展新的近似分析方法。本文针对船用C型夹层板,基于弹簧、扭簧与集中质量的等效方法,建立C型夹层板的声振耦合控制方程,利用空间谐波展开法,推导C型夹层结构的传声损失表达式,讨论夹层板系统参数对结构隔声性能的影响规律。结果表明,材料属性与夹层板结构面板的厚度对C型夹层板结构隔声性能的影响较大。同时,通过有限元仿真,验证了理论分析的有效性。

M型皱褶芯材夹层板隔声性能研究

作为先进复合材料夹层结构,皱褶芯材构型多样,先前研究大多围绕V型皱褶芯材展开,鲜有对其他构型的隔声性能研究。建立垂直入射声压激励下的四边简支M型皱褶芯材夹层板数值模型,基于有限元软件对其隔声性能进行数值仿真,并将理论预测的蜂窝夹层板隔声曲线与仿真结果进行对比;基于仿真模型,研究M型皱褶芯材夹层板结构的隔声性能,讨论皱褶芯材胞元几何参数对隔声性能的定性影响规律;研究双层芯材的M型皱褶芯材夹层板上下两层芯材的相对铺设错位、铺设角度对隔声性能的影响。结果表明:上下两层芯材在胞元Z形线步长方向错位叠放时隔声效果提高,且优于同面密度的单层皱褶芯材夹层板;在上下两层芯材相对铺设角度变化时,上下层芯材轴线垂直铺设时计权隔声量最大。

钢制金属I型夹芯板界面疲劳脱粘特性分析

[目的]针对金属I型夹芯板界面的脱粘失效破坏,开展金属夹芯板界面疲劳脱粘特性分析。[方法]基于内聚力模型理论,考虑时间历程、三维结构节点多自由度的损伤演化方程与收敛判定准则,开发适用于三维复杂结构的界面疲劳脱粘模拟程序;与焊接接头脱粘实验结果进行对比,验证所开发程序的准确性,并进一步对钢制金属I型夹芯板的界面疲劳脱粘行为进行数值模拟。[结果]结果显示,所开发的三维界面疲劳脱粘数值模拟程序与焊接接头脱粘实验间最大的模拟误差仅为14.05%;I型夹芯板承受面外载荷时,夹芯板界面处的脱粘破坏主要表现为沿焊缝方向的表面裂纹扩展,当裂纹扩展至夹芯板长度的70%左右时,裂纹开始贯穿腹板形成贯穿裂纹。[结论]所开发的三维复杂结构界面疲劳脱粘程序可以实现对金属夹芯板界面疲劳脱粘寿命的有效评估,对实际工程应用具有一定的指导意义。

{Co_(6)}簇加成的夹心型锗钨酸盐的合成、结构及电化学性质

通过水热反应合成了一个{Co_(6)}簇加成的夹心型锗钨酸盐:[Co(dien)_(2)]{[Co(dien)(H_(2)O)]_(2)[Co(dien)]_(2)[Co_(6)(en)_(2)(μ_(3)-OH)_(2)(H_(2)O)_(6)(GeW_(8)O_(31))_(2)]}·5.5H_(2)O(1),其中dien=diethylenetriamine,en=ethylenediamine。该化合物的阴离子是一个带状{Co_(6)}簇夹心的三明治型{Co_(6)}@{GeW8}2结构。通过单晶X射线衍射、元素分析、红外光谱、粉末X射线衍射和热重实验对该化合物进行了系统性地表征。通过循环伏安测试研究了该化合物的电化学性质,同时其在电催化还原亚硝酸盐实验中展现出良好的催化活性。

改进型金字塔状夹芯板耦合MAM结构的降噪设计与研究

为解决薄膜型声学超材料(membrane-type acoustic metamaterial,MAM)低频区间隔声频段较窄、耐久性差以及抗风险能力弱的问题,探讨MAM在变压器降噪领域的应用,现设计出一种金字塔状夹芯板和MAM耦合的降噪结构。采用有限元法研究耦合结构的隔声性能和声振特性,建立结构的声固耦合模型,分析结构的声传递损失和振动模态,并探究影响结构降噪的因素。研究表明,耦合结构有着优秀的中低频宽带隔声特性,且可以通过调整薄膜和薄板的参数改变结构的隔声特性。优化后的结构在110 kV变压器主噪声频点上的隔声量均能超过110 dB。

涂卷三道“夹芯式”全包围防水设防在上海古北SOHO商办项目屋面中的应用

上海古北SOHO新建商办项目,屋面防水设计采用了结构层和保温层上均设置防水层的做法,一共设置了涂料+卷材3道防水层,这样的设计结合了正置式屋面和倒置式屋面两种设防的优点,而避开了二者各自的缺点,全面防护结构层与保温层,形成一种新的“夹芯式”全包围防水做法,在应用中取得了良好效果。

双环三明治法在急性A型主动脉夹层根部吻合中的临床应用

目的探讨双环三明治法在急性A型主动脉夹层手术根部吻合中应用的疗效及安全性。方法2020年10月~2023年5月收治急性A型主动脉夹层病人103例,术中应用双环三明治法对主动脉根部进行处理,分析手术效果、短期心脏结构变化及术后短期并发症发生情况等。结果所有病人术中加针止血比例11.65%,围手术期红细胞输注量(2.95±1.97)U,血浆输注量(543.68±208.48)ml,血小板输注量(0.08±0.30)U。术后2周心脏超声主动脉瓣残存返流、心功能、心包积液均较术前明显改善,差异有统计学意义(P<0.05)。术后主动脉根部残存假腔比例明显减少,差异有统计学意义(P<0.05)。病人住院时间、插管时间、术后24小时引流均较少。术后二次开胸、脑梗塞、脑出血、血滤、气管切开、死亡等术后短期并发症发生概率均较低。结论急性A型主动脉夹层手术中应用双环三明治法行主动脉根部吻合可有效封闭根部的夹层假腔,降低主动脉内膜撕脱风险,手术安全性及疗效较为可靠。

内镜下组织胶“三明治”联合套扎术治疗2型胃底静脉曲张的研究

目的探讨内镜下组织胶“三明治”联合套扎术治疗2型胃底静脉曲张(GOV2)的临床疗效。方法选取2020年5月至2021年5月赣州市第五人民医院接诊的50例GOV2患者作为研究对象,根据治疗方法不同分为研究组与对照组,每组25例。研究组采用内镜下组织胶“三明治”联合套扎术,对照组采用内镜下组织胶+聚桂醇“三明治”夹心法。比较两组临床疗效、治疗前后门静脉血流动力学指标、术后并发症发生情况。结果两组治疗总有效率比较差异无统计学意义。治疗后,两组门静脉内径(PVD)、门静脉血流量(PBF)、胃左静脉(LGV)及脾静脉内径(SVD)均大于治疗前,门静脉血流速度(PVV)快于治疗前,门静脉压(PVP)低于治疗前,且研究组PVD、PBF、LGV及SVD均大于对照组,PVV快于对照组,PVP低于对照组,差异有统计学意义(P<0.05)。研究组术后并发症发生率低于对照组,差异有统计学意义(P<0.05)。结论内镜下组织胶“三明治”联合套扎术可有效改善GOV2患者血流动力学变化,减少术后并发症发生,值得临床推广应用。

Ⅰ型金属夹芯板试验模型缩比关系影响分析

为探索缩尺比对金属夹芯结构极限承载能力模型试验的影响规律,为典型金属夹芯结构试验模型的设计提供参考。针对Ⅰ型金属夹芯板的单轴压缩问题,通过非线性有限元对不同板厚缩比、不同长度缩比组合下的缩比模型极限承载特性进行对比分析,以获取Ⅰ型金属夹芯板缩比模型承载特性与缩尺比的关系。计算结果表明,板厚缩比与长度缩比相同时,不同缩比模型的极限承载特性成比例吻合;板厚缩比与长度缩比不一致时,板厚的变化将导致模型的失效模式产生偏差,降低缩比模型的计算结果吻合度,缩比模型的极限承载能力与缩尺比呈现非线性。因此,试验模型设计时应充分考虑缩尺比奇异性和承载特性非线性的影响,以提高缩比模型的相似度。

超声引导射频消融在较大乳腺纤维腺瘤治疗中的应用

目的探讨超声引导夹心水隔离技术辅助的射频消融(RFA)在较大乳腺纤维腺瘤(直径≥2 cm)治疗中的应用价值。方法选择2014年12月至2021年3月上海交通大学医学院附属仁济医院治疗的乳腺纤维腺瘤患者39例。患者均接受超声引导夹心水隔离技术辅助的RFA治疗,观察消融前、消融后即刻、消融后1个月、消融后3个月、消融后6个月肿瘤体积变化以及肿瘤体积缩小率,RFA后并发症发生情况。结果39例患者(42个肿瘤)的RFA治疗时间为(176.7±116.6)s。治疗前肿瘤最大直径为2.0~3.4 cm,消融前、消融后即刻、消融后1个月、消融后3个月、消融后6个月肿瘤体积分别为(3.16±2.08)mL、(2.19±1.42)mL、(1.24±0.93)mL、(0.64±0.59)mL、(0.26±0.31)mL,治疗后1、3、6个月超声检查显示肿瘤体积较消融前逐渐缩小,体积缩小率分别为(48.3±17.6)%、(77.8±17.1)%、(84.6±17.4)%。治疗后12个月36个肿瘤消融区消失,6个肿瘤仍可见消融区痕迹。39例患者均无严重治疗相关并发症发生。结论超声引导夹心水隔离技术辅助的RFA治疗直径≥2 cm的乳腺纤维腺瘤安全、微创、有效,适用于无法接受手术治疗的较大乳腺纤维腺瘤患者。