A New Sandwiched-type Polyoxotungstate Containing {Cd4} 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.     

Ultrathin Co3S4 Nanosheets that Synergistically Engineer Spin States and Exposed Polyhedra that Promote Water Oxidation under Neutral Conditions

Development of efficient and affordable electrocatalysts in neutral solutions is paramount importance for the renewable energy. Herein, we report that the oxygen evolution reaction (OER) performance of Co₃S₄ under neutral conditions can be enhanced by exposed octahedral planes and self‐adapted spin states in atomically thin nanosheets. A HAADF image clearly confirmed that the active octahedra with Jahn–Teller distortions were exposed exclusively. Most importantly, in the atomically thin nanosheets, the spin states of Co³⁺ in the octahedral self‐adapt from low‐spin to high‐spin states. As a result, the synergistic effect endow the Co₃S₄ nanosheets with superior OER performance, with exceptional low onset overpotentials of circa 0.31 V in neutral solutions, which is state‐of‐the‐art among inorganic non‐noble metal compounds.     

Reinforced Supramolecular Hydrogels from Attapulgite and Cyclodextrin Pseudopolyrotaxane for Sustained Intra‐Articular Drug Delivery

Injectable hydrogels for nonsteroidal anti‐inflammatory drugs’ (NSAIDs) delivery to minimize the side effects of NSAIDs and achieve long‐term sustained release at the targeted site of synovial joint are attractive for osteoarthritis therapy, but how to improve its mechanical strength remains a challenge. In this work, a kind of 1D natural clay mineral material, attapulgite (ATP), is introduced to a classical cyclodextrin pseudopolyrotaxane (PPR) system to form a reinforced supramolecular hydrogel for sustained release of diclofenac sodium (DS) due to its rigid, rod‐like morphology, and unique structure, which has great potential in tissue regeneration, repair, and engineering. Investigation on the interior morphology and rheological property of the obtained hydrogel points out that the ATP distributed in PPR hydrogel plays a role similar to the “reinforcement in concrete” and exhibits a positive effect on improving the mechanical properties of PPR hydrogel by regulating their interior morphology from a randomly distributed style to the well‐ordered porous frame structure. The hybrid hydrogels demonstrate good shear‐thinning and thixotropic properties, excellent biocompability, and sustained release behavior both in vitro and in vivo. Furthermore, preliminary in vivo treatment in an acute inflammatory rat model reveals that the ATP hybrid hydrogels present sustained anti‐inflammatory effect.     

HL-2M装置真空室预装阶段检漏试验

通过在加工现场和安装现场搭建的真空辅助系统、四极质谱计及氦检漏仪组成的检漏系统,运用残余气体分析和氦质谱检漏方法在冷态下对HL-2M真空室扇形段及真空室整体进行了真空检漏试验.对漏点进行修复后,测试了真空室的极限真空度和总漏气率等.真空室经过72h的抽气后,真空度达到3.7×10?5Pa,超过了1.0×10?4Pa的预...     

Graphene-nickel nitride hybrids supporting palladium nanoparticles for enhanced ethanol electrooxidation

Electrocatalysts for ethanol oxidation reaction(EOR)are generally limited by their poor durability because of the catalyst poisoning induced by the reaction intermediate carbon monoxide(CO).Therefore,the rapid oxidation removal of CO intermediates is crucial to the durability of EOR-based catalysts.Herein,in order to effectively avoiding the catalyst CO poisoning and improve the durability,the graphene-nickel nitride hybrids(AG-Ni₃N)were designed for supporting palladium nanoparticles(Pd/AG-Ni₃N)and then used for ethanol electrooxidation.The density functional theory(DFT)calculations demonstrated the introduction of AG-Ni₃N depresses the CO absorption and simultaneously promotes the adsorption of OH species for CO oxidation removal.The fabricated Pd/AG-Ni₃N catalyst distinctively exhibits excellent electroactivity with the mass catalytic activity of 3499.5 m A mg^-1 on EOR in alkaline media,which is around 5.24 times higher than Pd/C(commercial catalyst).Notably,the Pd/AG-Ni₃N hybrids display excellent stability and durability after chronoamperometric measurements with a total operation time of 150,000 s.     

Synthesis and Bioactivity of Novel Fluorinated Heteroaromatic Ureas

In order to find new urea cytokinins, a series of novel fluorinated heteroaromatic ureas have been designed and synthesized. The crystal structure of 3g was further determined by single crystal X-ray diffraction to obtain the structural feature of this class of urea compounds. The preliminary bioassay showed that some title compounds have good cytokinin activity.     

A Novel High Active TiO2/AC Composite Photocatalyst Prepared by Acid Catalyzed Hydrothermal Method

A high active novel TiO2/AC composite photocatalyst was prepared and used for phenol degradation. It was much more active than P-25 and exhibiting good decantability, less deactivation after several runs and less sensitive to pH change. Diffuse reflectance spectra (DRS) revealed that the electronic change in TiO2 did not occur by the addition of AC. Results of SEM and XRD suggested that better TiO2 distribution can be achieved when optimal AC content was adopted. The performance of the prepared TiO2/5AC catalyst revealed great practical potential in wastewater treatment field.     

器外预硫化型MoNiP/γ-Al2O3催化剂的二苯并噻吩加氢脱硫活性

 制备了两种器外预硫化型MoNiP/γ-Al2O3催化剂,并以二苯并噻吩为模型化合物考察了其加氢脱硫(HDS)活性,选择了传统的器内预硫化催化剂作为参比. 采用X射线衍射(XRD)、 高分辨透射电镜(HRTEM)和X射线光电子能谱(XPS)等手段对二者在加氢活性相方面的差别进行了研究. 结果表明,器外预硫化催化剂的HDS活性(最高达到99%)与器内预硫化催化剂相当,但是其加氢能力相对较弱. XRD与HRTEM等研究表明,器外预硫化催化剂所形成的MoS2片晶的堆垛层数相对较低,而Mo与S元素的XPS分析结果则说明相对器内预硫化催化剂,器外预硫化催化剂中不但Mo的硫化度较低,而且MoS2活性相的含量亦较少,而二者活性相之间的这种差异应是导致两类催化剂加氢活性不同的主要原因.     

牛血清白蛋白中氨基酸的高效液相色谱荧光测定及质谱鉴定

利用新型荧光试剂1,2苯-并-3,4二-氢咔唑-9乙-基氯甲酸酯(BCEOC)作为柱前衍生化试剂,在Hypersil BDS C18(4.6 mm×200 mm,5μm)反相色谱柱上,采用梯度洗脱对氨基酸衍生物进行了分离检测。检测的激发和发射波长分别为λex=333 nm,λem=390 nm。采用电喷雾离子源(ESI Source),实现了牛血清白蛋白中氨基酸的定性测定。荧光定量检测的线性回归系数均大于0.999;检出限为6.3~117.6 fmo。l