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Synthesis and Characterization of New Palladium(ll) Complexes Containing 4,5-dimethyl-2,2'-bipyridine: X-ray Crystal Structure of Bis(4-methyl pyrdine)-4,5- dimethyl-2,2'-bipyridine palladium (11) Perchlorate
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作者 Bashir EI-Gnidi Abdulhafid M. Belazi R. D. Gillard 《Journal of Chemistry and Chemical Engineering》 2012年第8期673-681,共9页
New heteroleptic and homoleptic complexes of the type[Pd(4,5-dmbipy)C12], [Pd(4,5-dmbipy)L2], and [Pd(4,5-dimebipy)2]2+ (L = Pyridine or 4-methylpyridine(4-picoline), bipy = 2,2'-bipyridine, and 4,5-dimebip... New heteroleptic and homoleptic complexes of the type[Pd(4,5-dmbipy)C12], [Pd(4,5-dmbipy)L2], and [Pd(4,5-dimebipy)2]2+ (L = Pyridine or 4-methylpyridine(4-picoline), bipy = 2,2'-bipyridine, and 4,5-dimebipy = 4,5-dimethyl-2,2'-bipyridine) were synthesized and characterized by IH NMR and elemental analysis. The crystal structure of bis(4-methylpyridine)-4,5- dimethyl-2,2'-bipyridinepalladium(II)perchlorate [Pd(4,5-dmbipy)(4-pic)2](CIO4)2 was also determined by single crystal X-ray diffraction. This complex crystallized in the triclinic crystal system and space group PI with a = 9.562 (2), b = 11.326 (4), c = 15.0120 (10) A°; α = 70.940°, β= 77.60 (2), γ= 67.86 (2) and z = 4. The Pd (II) in square planar environment showed a small distortion towards tetrahedral through one coordinated bipyridine ring twisting with respect to the other. 展开更多
关键词 4 5-dimethyl-2 2'-bipyridine palladium(II) complexes single crystal.
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Preparation of a zeolite-palladium composite membrane for hydrogen separation:Influence of zeolite film on membrane stability
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作者 Hongmei Wu Xinyu Liu Yu Guo 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第8期44-52,共9页
With the development of hydrogen energy,palladium-based membranes have been widely used in hydrogen separation and purification.However,the poor chemical stability of palladium composite membranes limits their commerc... With the development of hydrogen energy,palladium-based membranes have been widely used in hydrogen separation and purification.However,the poor chemical stability of palladium composite membranes limits their commercial applications.In this study,a zeolite-palladium composite membrane with a sandwich-like structure was obtained by using a TS-1 zeolite film grown on the surface of palladium membrane.The membrane microstructure was characterized by SEM and EDX.The effects of the TS-1 film on the hydrogen permeability and stability of palladium composite membrane were investigated in details.Benefited from the protection of the TS-1 zeolite film,the stability of palladium composite membrane was enhanced.The results indicate that the TS-1-Pd composite membrane was stable after eight cycles of the temperature exchange cycles between 773 K and 623 K.Especially,the loss of hydrogen permeance for TS-1-Pd composite membrane was much smaller than that of the pure palladium membrane when the membrane was tested in the presence of C3H6atmosphere.It indicated that the TS-1-Pd composite membrane had better chemical stability in comparison with pure palladium membrane,owing to its sandwich-like structure.This work provides an efficient way for the deposition of zeolite film on palladium membrane to enhance the membrane stability. 展开更多
关键词 palladium membrane Zeolite film Hydrogen separation STABILITY
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MOF-assisted Synthesis of Dual-atom Palladium Catalysts for Acetylene Semi-hydrogenation
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作者 Chen Jie Xu Yuebing +2 位作者 Qi Jian Liu Bing Liu Xiaohao 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第3期42-52,共11页
The selective removal of trace acetylene in ethylene feed gas is of great significance in the petrochemicalindustry;however, there are still challenges in designing and developing high-performance catalysts. Here, a M... The selective removal of trace acetylene in ethylene feed gas is of great significance in the petrochemicalindustry;however, there are still challenges in designing and developing high-performance catalysts. Here, a MOFassistedencapsulation strategy was adopted for the precise synthesis of diatomic Pd2 sites on a ZnO support. When usedfor the acetylene semi-hydrogenation reaction, the dual-atom Pd2-ZnO catalyst exhibited improved catalytic performance,achieving complete conversion of acetylene at 125 °C with an 89% selectivity to ethene, as compared to Pd single-atom andnanoparticles. This enhancement was mainly attributed to the catalyst’s ability to dissociate H2 and facilitate the desorptionof intermediate C2H4. Moreover, the strong interaction between the support and the diatomic Pd sites was responsible for thecatalyst’s excellent stability during the long-term reaction. 展开更多
关键词 dual-atom palladium acetylene semi-hydrogenation MOFs hydrogen dissociation intermediate
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Low palladium content CeO_(2)/ZnO composite for acetone sensor with sub-second response prepared by ultrasonic method
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作者 CHEN Xu-jie XING Qiao-ling +2 位作者 TANG Xuan CAI Yong ZHANG Ming 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2137-2149,共13页
In practical applications,noble metal doping is often used to prepare high performance gas sensors,but more noble metal doping will lead to higher preparation costs.In this study,CeO_(2)/ZnO-Pd with low palladium cont... In practical applications,noble metal doping is often used to prepare high performance gas sensors,but more noble metal doping will lead to higher preparation costs.In this study,CeO_(2)/ZnO-Pd with low palladium content was prepared by ultrasonic method with fast response and high selectivity for acetone sensing.With the same amount of palladium added,the selectivity coefficient of CeO_(2)/ZnO-Pd is 1.88 times higher than that of the stirred sensor.Compared with the pure PdO-doped CeO_(2)/ZnO-PdO material,the content of Pd in CeO_(2)/ZnO-PdO is about 30%of that in CeO_(2)/ZnO-PdO,but the selectivity coefficient for acetone is 2.56 times higher.The CeO_(2)/ZnO-Pd sensor has a higher response(22.54)to 50×10^(−6) acetone at 300℃and the selectivity coefficient is 2.57 times that of the CeO_(2)/ZnO sensor.The sensor has a sub-second response time(0.6 s)and still has a 2.36 response to 330×10^(−9) of acetone.Ultrasonic doping makes Pd particles smaller and increases the contact area with gas.Meanwhile,the composition of n-p-n heterojunction and the synergistic effect of Pd/PdO improve the sensor performance.It shows that ultrasonic Pd doping provides a way to improve the utilization rate of doped metals and prepare highly selective gas sensors. 展开更多
关键词 low palladium sub-second responce ultrasonic method acetone sensor heterojunction
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Controlling Reactivity of Palladium Amides for Selective Carbonylation towards Urea and Oxamide Derivatives
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作者 WANG Jin-hui CAO Yan-wei HE Lin 《分子催化(中英文)》 CAS CSCD 北大核心 2024年第4期297-308,共12页
Carbonylation reactions,crucial for carbonyl group incorporation,struggle with the inherent complexity of achieving selective mono-or double-carbonylation on single substrates,often due to competing reaction pathways.... Carbonylation reactions,crucial for carbonyl group incorporation,struggle with the inherent complexity of achieving selective mono-or double-carbonylation on single substrates,often due to competing reaction pathways.Herein,our study introduces a strategy employing palladium amides,harnessing their unique reactivity control,to direct the selective carbonylation of amines for the targeted synthesis of urea and oxamide derivatives.The palladium amide structure was elucidated using single-crystal X-ray diffraction.Controlled experiments and cyclic voltammetry studies further elucidate that the oxidation of palladium amide or its insertion into a carbonyl group diverges into distinct pathways.By employing sodium percarbonate as an eco-friendly oxidant and base,we have successfully constructed a switchable carbonylation system co-catalyzed by palladium and iodide under room temperature.The utilizing strategy in this study not only facilitates effective control over reaction selectivity but also mitigates the risk of explosions,a critical safety concern in traditional carbonylation methods. 展开更多
关键词 selectivity control palladium catalysis oxidative carbonylation AMINOCARBONYLATION green reagents
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Preparation of palladium-based catalyst by plasma-assisted atomic layer deposition and its applications in CO_(2) hydrogenation reduction
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作者 唐守贤 田地 +4 位作者 李筝 王正铎 刘博文 程久珊 刘忠伟 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第6期31-39,共9页
Supported Pd catalyst is an important noble metal material in recent years due to its high catalytic performance in CO_(2)hydrogenation.A fluidized-bed plasma assisted atomic layer deposition(FP-ALD) process is report... Supported Pd catalyst is an important noble metal material in recent years due to its high catalytic performance in CO_(2)hydrogenation.A fluidized-bed plasma assisted atomic layer deposition(FP-ALD) process is reported to fabricate Pd nanoparticle catalyst over γ-Al_(2)O_(3)or Fe_(2)O_(3)/γ-Al_(2)O_(3)support,using palladium hexafluoroacetylacetonate as the Pd precursor and H_(2)plasma as counter-reactant.Scanning transmission electron microscopy exhibits that highdensity Pd nanoparticles are uniformly dispersed over Fe_(2)O_(3)/γ-Al_(2)O_(3)support with an average diameter of 4.4 nm.The deposited Pd-Fe_(2)O_(3)/γ-Al_(2)O_(3)shows excellent catalytic performance for CO_(2)hydrogenation in a dielectric barrier discharge reactor.Under a typical condition of H_(2)to CO_(2)ratio of 4 in the feed gas,the discharge power of 19.6 W,and gas hourly space velocity of10000 h^(-1),the conversion of CO_(2)is as high as 16.3% with CH_(3)OH and CH4selectivities of 26.5%and 3.9%,respectively. 展开更多
关键词 atomic layer deposition CO_(2)hydrogenation palladium based catalyst
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Inner-pore reduction nucleation of palladium nanoparticles in highly conductive wurster-type covalent organic frameworks for efficient oxygen reduction electrocatalysis 被引量:1
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作者 Weiwen Wang Lu Zhang +4 位作者 Tianping Wang Zhen Zhang Xiangnan Wang Chong Cheng Xikui Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第2期543-552,I0014,共11页
Covalent organic frameworks(COFs)have emerged as a class of promising supports for electrocatalysis because of their advantages including good crystallinity,highly ordered pores,and structural diversity.However,their ... Covalent organic frameworks(COFs)have emerged as a class of promising supports for electrocatalysis because of their advantages including good crystallinity,highly ordered pores,and structural diversity.However,their poor conductivity represents the main obstruction to their practical application.Here,we reported a novel synthesis strategy for synergistically endowing a triphenylamine-based COFs with improved electrical conductivity and excellent catalytic activity for oxygen reduction,via the in-situ redox deposition and confined growth of palladium nanoparticles inside the porous structure of COFs using reductive triphenylamine frameworks as reducing agent;meanwhile,the triphenylamine unit was oxidized to radical cation structure and affords radical cation COFs with conductivity as high as3.2*10^(-1) S m^(-1).Such a uniform confine palladium nanoparticle on highly conductive COFs makes it an efficient electrocatalyst for four-electron oxygen reduction reaction(4e-ORR),showing excellent activities and fast kinetics with a remarkable half-wave potential(E_(1/2))of 0.865 V and an ultralow Tafel slope of 39.7 mV dec^(-1) in alkaline media even in the absence of extra commercial conductive fillers.The generality of this strategy was proved by preparing the different metal and metal alloy nanoparticles supported on COFs(Au@COF,Pt@COF,AuPd@COF,AgPd@COF,and PtPd@COF)using reductive triphenylamine frameworks as reducing agent.This work not only provides a facile strategy for the fabrication of highly conductive COF supported ORR electrocatalysts,but also sheds new light on the practical application of Zn-air battery. 展开更多
关键词 Covalent organic frameworks Wurster-type structure In-situ reduction nucleation palladium nanoparticles Oxygen reduction electrocatalysis
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足三里穴位注射黄芪注射液联合肺康复训练对老年慢性阻塞性肺疾病病人抗菌肽LL-37和免疫功能的影响 被引量:1
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作者 邓在勤 周海波 《实用老年医学》 CAS 2024年第1期44-48,共5页
目的 研究足三里穴位注射黄芪注射液联合肺康复训练对老年COPD稳定期病人的疗效、血清抗菌肽LL-37水平、炎症因子及外周血T淋巴细胞亚群的影响。方法 选择98例老年COPD稳定期病人,根据治疗方法分为黄芪组(50例)和对照组(48例)。对照组... 目的 研究足三里穴位注射黄芪注射液联合肺康复训练对老年COPD稳定期病人的疗效、血清抗菌肽LL-37水平、炎症因子及外周血T淋巴细胞亚群的影响。方法 选择98例老年COPD稳定期病人,根据治疗方法分为黄芪组(50例)和对照组(48例)。对照组予以肺康复训练及常规西药治疗,黄芪组在对照组基础上予以足三里穴位注射黄芪注射液,疗程均为12周。比较2组治疗前后肺功能、6分钟步行试验(6MWT)结果、改良版英国医学研究委员会呼吸问卷(mMRC)呼吸困难程度分级,血清抗菌肽LL-37、TNF-α、IL-6、CRP水平及T淋巴细胞亚群变化。结果 2组治疗后肺功能(FVC、FEV1、FEV1%pred、FEV1/FVC)、6MWT结果及mMRC分级均较治疗前明显改善(P<0.05),且黄芪组较对照组改善更为明显(P<0.05)。2组治疗后血清抗菌肽LL-37、CD3^(+)T淋巴细胞、CD4^(+)T淋巴细胞及CD4^(+)/CD8^(+)水平均较治疗前升高,且黄芪组高于对照组(P<0.05);2组治疗后TNF-α、IL-6、CRP水平均低于治疗前,且黄芪组低于对照组(P<0.05)。结论 足三里穴位注射黄芪注射液联合肺康复训练可改善老年COPD稳定期病人的肺功能和运动耐力,提高血清抗菌肽LL-37水平并改善免疫功能。 展开更多
关键词 慢性阻塞性肺疾病 肺康复 抗菌肽ll-37 T淋巴细胞亚群 黄芪注射液 穴位注射
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Highly reactive and reusable heterogeneous activated carbons-based palladium catalysts for Suzuki-Miyaura reaction
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作者 Yifan Jiang Bingqi Xie Jisong Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第8期165-172,共8页
Suzuki-Miyaura reaction of aryl halides with phenylboronic acid using a heterogeneous palladium catalyst based on activated carbons(AC) was systematically investigated in this work. Two different reaction modes(batch ... Suzuki-Miyaura reaction of aryl halides with phenylboronic acid using a heterogeneous palladium catalyst based on activated carbons(AC) was systematically investigated in this work. Two different reaction modes(batch procedure and continuous-flow procedure) were used to study the variations of reaction processing. The heterogeneous catalysts presented excellent reactivity and recyclability for iodobenzene and bromobenzene substrates in batch mode, which can be attributed to stabilization of Pd nanoparticles by the thiol and amino groups on the AC supports. However, significant dehalogenation in the reaction mixture and Pd leaching from the heterogeneous catalysts were observed in continuous-flow mode.This unique phenomenon in continuous-flow mode resulted in a dramatic decline in reaction selectivity and durability of heterogeneous catalysts comparing with that of batch mode. In addition, the heterogeneous Pd catalysts with thiol-and amino-modified AC supports exhibited different reactivity and durability in batch and continuous-flow mode owing to the difference of interaction between Pd species and AC supports. 展开更多
关键词 Suzuki-Miyaura reaction Heterogeneous palladium catalysts Activated carbon Thiol-and amino-functionalization Catalyst support Packed bed
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植物乳杆菌Zhang-LL与马克斯克鲁维酵母菌M3共发酵葡萄汁酵素的工艺优化
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作者 董双佳 刘慧 +3 位作者 金君华 张红星 杨竹娘 谢远红 《北京农学院学报》 2024年第1期77-83,共7页
【目的】以葡萄汁为原料,植物乳杆菌Zhang-LL及马克斯克鲁维酵母M3为发酵菌株,优化葡萄汁酵素的发酵工艺条件。【方法】比较植物乳杆菌Zhang-LL和马克斯克鲁维酵母M3在葡萄汁中的不同接种方式对益生菌活菌数和DPPH清除率的影响,筛选葡... 【目的】以葡萄汁为原料,植物乳杆菌Zhang-LL及马克斯克鲁维酵母M3为发酵菌株,优化葡萄汁酵素的发酵工艺条件。【方法】比较植物乳杆菌Zhang-LL和马克斯克鲁维酵母M3在葡萄汁中的不同接种方式对益生菌活菌数和DPPH清除率的影响,筛选葡萄汁酵素最优接种发酵方式。进一步通过单因素试验及响应面试验,优化葡萄汁酵素最佳发酵工艺条件。【结果】植物乳杆菌Zhang-LL和马克斯克鲁维酵母M3共发酵可以显著提高葡萄汁酵素中益生菌活菌数和DPPH清除率;植物乳杆菌Zhang-LL和马克斯克鲁维酵母M3共发酵的最佳工艺条件为:按照1∶1比例接种,初始接种量5.00 lg CFU/mL、大豆蛋白胨添加量0.46%、34℃发酵18 h,植物乳杆菌Zhang-LL活菌数达6.60×10^(8)CFU/mL,马克斯克鲁维酵母M3活菌数达8.20×10^(7)CFU/mL,酵素DPPH清除率85.25%。【结论】乳酸菌与酵母菌协同发酵,在缩短发酵时间的同时还能达到较高的活菌数和DPPH清除率,可为葡萄汁酵素的工业化制备及后续多功能产品研发提供理论依据。 展开更多
关键词 葡萄酵素 植物乳杆菌Zhang-ll 马克斯克鲁维酵母M3 共培养
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老年慢性心力衰竭患者血清LL37和SSC5D水平检测对预后的评估价值
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作者 安国印 陈润祥 +1 位作者 吴晶晶 廖占玲 《现代检验医学杂志》 CAS 2024年第5期80-84,91,共6页
目的探讨血清抗菌肽LL37(LL37)和人可溶性富含半胱氨酸结构域的清道夫受体蛋白(soluble scavengerreceptor cysteine-rich domain-containing protein,SSC5D)在老年慢性心力衰竭(chronic heart failure,CHF)中的表达及对预后的评估价值... 目的探讨血清抗菌肽LL37(LL37)和人可溶性富含半胱氨酸结构域的清道夫受体蛋白(soluble scavengerreceptor cysteine-rich domain-containing protein,SSC5D)在老年慢性心力衰竭(chronic heart failure,CHF)中的表达及对预后的评估价值。方法选取上海交通大学医学院附属苏州九龙医院2017年1月~2022年1月收治的100例CHF患者为CHF组,根据预后情况将患者分为预后良好组(n=60)和预后不良组(n=40)。另选取100例健康体检者为对照组。酶联免疫吸附试验(ELISA)检测血清LL37和SSC5D水平。比较CHF组和对照组血清LL37和SSC5D水平差异;Spearman分析血清LL37和SSC5D相关性;Kaplan-Meier生存曲线分析血清LL37和SSC5D表达与CHF患者预后的关系;COX分析影响CHF患者预后的因素。采用ROC曲线分析血清LL37和SSC5D对老年CHF患者预后不良的预测价值。结果CHF组血清LL37(771.38±158.25 ng/ml)和SSC5D(15789.35±1306.25 pg/ml)水平高于对照组(526.23±115.58ng/ml,8938.72±858.29 pg/ml),差异具有统计学意义(t=12.510,43.830,均P<0.001)。Spearman相关性分析结果显示,CHF患者血清LL37与SSC5D水平呈显著正相关(r=0.629,P<0.001);CHF患者血清LL37,SSC5D水平与NYHA心功能分级呈显著正相关(r=0.776,0.751,均P<0.001)。高水平LL37组生存率显著低于低水平LL37组(38.18%vs 86.67%),差异具有统计学意义(Log rankχ^(2)=24.242,P<0.001);高水平SSC5D组生存率显著低于低水平SSC5D组(37.74%vs 85.10%),差异具有统计学意义(Log rankχ^(2)=23.291,P<0.001)。预后不良组>70岁占比、NYHA心功能分级Ⅲ+Ⅳ级占比、血清LL37和SSC5D水平高于预后良好组,差异具有统计学意义(χ^(2)=10.774,4.118,t=4.723,14.059,均P<0.05)。多因素COX分析结果表明,年龄>70岁(OR=1.515,95%CI:1.224~1.858)、NYHA心功能Ⅲ+Ⅳ分级(OR=1.236,95%CI:1.198~1.963)、高水平LL37(OR=1.705,95%CI:1.163~2.582)和高水平SSC5D(OR=1.591,95%CI:1.052~1.916)是影响CHF患者预后的独立危险因素(均P<0.05)。ROC曲线分析显示,血清LL37和SSC5D联合预测老年CHF预后不良的曲线下面积大于血清LL37和SSC5D单独检测,差异具有统计学意义(Z=2.834,2.168,P=0.005,0.030)。结论CHF患者血清LL37和SSC5D水平升高,两者均是CHF患者预后不良危险因素,可作为临床评估CHF预后指标。 展开更多
关键词 抗菌肽ll37 人可溶性富含半胱氨酸结构域的清道夫受体蛋白 慢性心力衰竭
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抗菌肽LL⁃37在骨质疏松症中的作用机制研究进展
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作者 冷鹏 唐晓军 《中国骨质疏松杂志》 CAS CSCD 北大核心 2024年第3期454-457,共4页
抗菌肽(antimicrobial peptides,AMPS)是一种宿主防御肽,既往主要关注其抗细菌及抗病毒作用,进一步研究发现AMPS可在成骨、破骨、免疫、促进血管生成等多个途径调控骨代谢、参与骨质疏松症的发生发展。本文旨在总结AMPS在骨代谢中的调... 抗菌肽(antimicrobial peptides,AMPS)是一种宿主防御肽,既往主要关注其抗细菌及抗病毒作用,进一步研究发现AMPS可在成骨、破骨、免疫、促进血管生成等多个途径调控骨代谢、参与骨质疏松症的发生发展。本文旨在总结AMPS在骨代谢中的调控机制,探讨其对骨质疏松症的影响为AMPS治疗骨质疏松症提供理论依据。 展开更多
关键词 抗菌肽ll⁃37 骨质疏松症 骨代谢
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Palladium nanoparticles in cross-linked polyaniline as highly efficient catalysts for Suzuki-Miyaura reactions 被引量:4
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作者 樊海鹏 祁正亮 +3 位作者 随德君 毛飞 陈日志 黄军 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第3期589-596,共8页
Palladium nanoparticles supported on cross-linked polyaniline with bulky phosphorus ligands were developed.These catalysts showed high efficiency in the Suzuki-Miyaura reaction of aryl chlorides and bromides with phen... Palladium nanoparticles supported on cross-linked polyaniline with bulky phosphorus ligands were developed.These catalysts showed high efficiency in the Suzuki-Miyaura reaction of aryl chlorides and bromides with phenylboronic acids.Aryl chlorides and bromides with functional groups,such as CN,MeO,CHO,MeCO and NO_2,were converted to the corresponding biphenyls in high yields with catalyst loading.Additionally,the catalysts combined high activity with good reusability;they could be used at least five times for the Suzuki-Miyaura coupling reaction. 展开更多
关键词 palladium Heterogeneous catalyst POLYANILINE Suzuki-Miyaura coupling reactions BIPHENYLS
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Ionic palladium complex as an efficient and recyclable catalyst for the carbonylative Sonogashira reaction 被引量:1
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作者 杨妲 王栋梁 +4 位作者 刘欢 赵小莉 路勇 赖时军 刘晔 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第3期405-411,共7页
The neutral palladium(Ⅱ) complex bis-[1-(5'-diphenylphosphinothiazol-2'-yl)-imidazolyl]dichloropalladium(Ⅱ)(1A) ligated by thiazolylimidazolyl-based phosphine(L1) in which thiazolylimidazolyl acted as an... The neutral palladium(Ⅱ) complex bis-[1-(5'-diphenylphosphinothiazol-2'-yl)-imidazolyl]dichloropalladium(Ⅱ)(1A) ligated by thiazolylimidazolyl-based phosphine(L1) in which thiazolylimidazolyl acted as an S- and N-donor provider with weak coordinating nature,and the ionic complex bis-[1-(5'-diphenylphosphinothiazol-2'-yl)-3-methylimidazolium]dichloropalladium(Ⅱ) trifluoromethanesulfonate(2A) ligated by thiazolylimidazolium-based phosphine(L2) after quaternization of L1 using methyl trifluoromethanesulphonate were synthesized.It was found that the introduced positive charges and strong electron-withdrawing effect in 2A not only led to changes in the configuration and structural stability of the complex,but also lowered its catalytic performance in carbonylative Sonogashira reactions.These effects reveal the important role of the N-donor in 1A.In addition,as an ionic palladium complex,2A combined with the room-temperature ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate could be recycled eight times as the catalyst in carbonylative Sonogashira reactions without detectable metal leaching. 展开更多
关键词 Ionic phosphine ligand palladium complex Carbonylative Sonogashira reaction Ionic liquid
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Green synthesis and characterization of palladium nanoparticles and its conjugates from solanum trilobatum leaf extract 被引量:4
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作者 Amarnath Kanchana Saveetha Devarajan Senniyanallur Rathakrishnan Ayyappan 《Nano-Micro Letters》 SCIE EI CAS 2010年第3期169-176,共8页
An important area of research in nanotechnology deals with the synthesis of nanoparticles of different chemical compositions,sizes and controlled monodispersity.Currently,there is a growing need to develop environment... An important area of research in nanotechnology deals with the synthesis of nanoparticles of different chemical compositions,sizes and controlled monodispersity.Currently,there is a growing need to develop environmentally benign nanoparticle synthesis in which no toxic chemicals are used in the synthesis protocol.Palladium nanoparticles(Pd Np) are of interest because of their catalytic properties and affinity for hydrogen.Our protocol for the phyto-synthesis of Pd Np under moderate p H and room temperature offers a new means to develop environmentally benign nanoparticles.Solanum trilobatum is enlightened in our present study as it is enriched with phytochemicals to reduce palladium chloride ions.Poly MVA a dietary supplement based on the nontoxic chemotherapeutic lipoic acid-palladium complex(LA-Pd) is been hypothesized as the new paradigm of cancer therapy.Hence forth we successfully conjugated lipoic acid(S-Pd Np-LA) and vitamins(S-Pd Np-Vitamin-LA) to palladium nanoparticles synthesised from Solanum trilobatum leaf extract.These nanoparticles(S-Pd Np,S-Pd Np-LA,S-Pd Np-Vitamin-LA) were characterized with UV-Vis Spectroscopy,SEM and FTIR analysis,which revealed that S-Pd Np are polydisperse and of different morphologies ranging from 60?70 nm(S-Pd Np),65?80 nm(S-Pd Np-LA) and 75?100 nm(S-Pd Np-Vitamin-LA) in size. 展开更多
关键词 NANOPARTICLES palladium Lipoic acid palladium lipoic acid complex Poly-MVA Green synthesis Solanum trilobatum
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DISLOCATION DISSOCIATIONS AND FAULTENERGIES IN Ni_3Al ALLOYS DOPED WITH PALLADIUM 被引量:16
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作者 J.Sun C.S.Lee J.K.L.Lai 《中国有色金属学会会刊:英文版》 CSCD 1999年第S1期87-94,共8页
Dislocation structures in polycrystalline Ni 3Al alloy doped with palladium deformed at room temperature have been investigated by transmission electron microscopy. The structure consists mainly of dislocations dissoc... Dislocation structures in polycrystalline Ni 3Al alloy doped with palladium deformed at room temperature have been investigated by transmission electron microscopy. The structure consists mainly of dislocations dissociated into a /2〈011〉 super partials bounding an anti phase boundary (APB). Dislocations dissociated into a /3〈112〉 super Shockley partials bounding a superlattice intrinsic stacking fault (SISF) are also common debris. The majority of the SISFs are truncated loops, i.e. the partials bounding the SISF are of similar Burgers vector. These faulted loops are generated from APB coupled dislocations, according to a mechanism for formation of SISFs proposed by Suzuki et al , and recently modified by Chiba et al . The APB energies for {111} and {010} slip planes are measured to be 144±20 mJ/m 2 and 102±11 mJ/m 2 respectively, and the SISF energy has been estimated to be 12 mJ/m 2 in this alloy. It is concluded that the dislocation structure in Ni 74.5 Pd 2Al 23.5 alloy deformed at room temperature is similar to that in binary Ni 3Al, and the difference in fault energies between these two alloys is small. Thus, it seems unlikely that the enhancement of ductility of Ni 74.5 Pd 2Al 23.5 results from only such a small decrease of the ordering energy of the alloy. SISF bounding dislocations also have no apparent influence on the ductilization of Ni 74.5 Pd 2Al 23.5 alloy. 展开更多
关键词 Ni_(3)Alalloys palladium doption dislocation dissociations fault energies
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Influence of CeO_2 and La_2O_3 on properties of palladium catalysts used for emission control of natural gas vehicles 被引量:6
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作者 Yile Li Xiaoyu Zhang Enyan Long Hongmei Li Dongdong Wu Li Cai Maochu Gong Yaoqiang Chen 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2009年第4期415-420,共6页
Pd/YZ-Al2O3 (Y and Zr modified Al2O3, and hereafter, labelled as A1) catalysts with 4 wt% additive CeO2 and/or La2O3 were prepared and characterized by X-ray photoelectron spectroscopy (XPS), NO-temperature progra... Pd/YZ-Al2O3 (Y and Zr modified Al2O3, and hereafter, labelled as A1) catalysts with 4 wt% additive CeO2 and/or La2O3 were prepared and characterized by X-ray photoelectron spectroscopy (XPS), NO-temperature programmed desorption (NO-TPD), Nz-adsorption/desorption (Branauer-Emmet-Teller BET method), X-ray diffraction (XRD) and CO-chemisorption. Catalytic activities for CH4, CO and NO conversion were tested in a gas mixture simulated the emissions from natural gas vehicles (NGVs) operated under stoichiometric conditions. The results indicated that all catalysts exhibited excellent catalytic performances for CH4 and CO oxidation and the promoting effect of CeO2 or La2O3 was significant for NO conversion. XPS results showed that the electron density around Pd was increased by CeO2 and/or La2O3, the binding energy of Pd 3d decreased as the order: Pd/Al 〉 Pd/Ce/Al 〉 Pd/La/Al 〉 Pd/CeLa/Al. The electron-rich Pd showed Rh-like catalytic properties which exhibited good activity for the reduction of NO. NO-TPD results showed that the addition of CeO2 and/or La2O3 increased NO adsorption on surface, and promoted the conversion of NO. 展开更多
关键词 NGVs under stoichiometric condition palladium catalyst XPS NO-TPD NO conversion methane conversion
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Preparation and Characterization of Palladium Colloidal Nanoparticles by Thermal Decomposition of Palladium Acetate with Microwave Irradiation 被引量:4
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作者 Yixian CHEN, Baolin HE and Hanfan LIU Hubei Key Laboratory for Catalysis and Material Science, University of South-Central for Nationalities, Wuhan 430074, China PCLCC, State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2005年第2期187-190,共4页
A series of solvent-stabilized palladium colloidal nanoparticles were prepared via thermal decomposition of palladium acetate methylisobutylketone (MIBK) solution in the presence of alkali and alcohol with microwave i... A series of solvent-stabilized palladium colloidal nanoparticles were prepared via thermal decomposition of palladium acetate methylisobutylketone (MIBK) solution in the presence of alkali and alcohol with microwave irradiation. The colloidal nanoparticles were characterized with TEM, XPS and XRD. The average diameters of nanoparticles increase from 30 to 40 nm with the increase in concentration of palladium acetate. TEM and XRD observation demonstrated that the palladium colloidal nanoparticles were clusters agglomerated from hundreds of smaller palladium crystallines with size of 3-4 nm. The influence of the concentrations of alkali and alcohol to the particle size was also discussed. 展开更多
关键词 Thermal decomposition MICROWAVE palladium acetate Methylisobutylketone
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Study on Physical and Chemical Behaviors of Rare Earths in Preparing Ceramic Tube Supported Palladium Film by Electroless Plating 被引量:4
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作者 蒋柏泉 叶志强 彭健 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第z2期259-262,共4页
The rare earths of ytterbium, lanthanum, praseodymium, neodymium and their binary mixtures were respectively added into the traditional electroless plating solution to prepare thin palladium film on the inner surface ... The rare earths of ytterbium, lanthanum, praseodymium, neodymium and their binary mixtures were respectively added into the traditional electroless plating solution to prepare thin palladium film on the inner surface of porous ceramic tube. The experimental results shows that the addition of rare earths increases palladium deposition rates and the binary mixtures are superior to the single rare earths and the mixture of ytterbium-lanthanum is the most efficient. Adding the mixture of ytterbium-lanthanum can also reduce the plating temperature by 10 ~ 20℃, shrink the metal crystal size and improve the film densification compared to those by traditional electroless plating. A thin palladium film with 5μm was prepared and the film made a highly pure hydrogen with a molar fraction of more than 99.97% from a H2-N2 gas mixture. More attentions were paid to analyze the physical and chemical behaviors of the rare earths in palladium film preparation. 展开更多
关键词 electroless plating palladium hydrogen separation rare earths
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Palladium,Platinum and Gold Concentrations in Fengshan Porphyry Cu-Mo Deposit,Hubei Province,China 被引量:3
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作者 WANG Minfang DENG Xiaodong BI Shijian LI Zhanke 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第5期893-901,共9页
The Fengshan porphyry-skarn copper-molybdenum (Cu-Mo) deposit is located in the south-eastern Hubei Province in east China. Cu-Mo mineralization is hosted in the Fengshan granodiorite porphyry stock that intruded th... The Fengshan porphyry-skarn copper-molybdenum (Cu-Mo) deposit is located in the south-eastern Hubei Province in east China. Cu-Mo mineralization is hosted in the Fengshan granodiorite porphyry stock that intruded the Triassic Daye Formation carbonate rocks in the early Cretaceous (-140 Ma), as well as the contact zone between granodiorite porphyry stock and carbonate rocks, forming the porphyry-type and skaru-type association. The Fengshan granodiorite stock and the immediate country rocks are strongly fractured and intensely altered by hydrothermal fluids. In addition to intense skarn alteration, the prominent alteration types are potassic, phyllic, and propylitic, whereas argiilation is less common. Mineralization occurs as veins, stock works, and disseminations, and the main ore minerals are chalcopyrite, pyrite, molybdenite, bornite, and magnetite. The contents of palladium, platinum and gold (Pd, Pt and Au) are determined in nine samples from fresh and mineralized granodiorite and different types of altered rocks. The results show that the Pd content is systematically higher than Pt, which is typical for porphyry ore deposits worldwide. The Pt content ranges from 0.037 tol.765 ppb, and the Pd content ranges between 0.165 and 17.979 ppb. Pd and Pt are more concentrated in porphyry mineralization than skarn mineralization, and have negative correlations with Au. The reconnaissance study presented here confirms the existence of Pd and Pt in the Fengshan porphyry-skarn Cu-Mo deposit. When compared with intracontinent and island arc geotectonic settings, the Pd, Pt, and Au contents in the Fengshan porphyry Cu-Mo deposit in the intracontinent is lower than the continental margin types and island are types. A combination of available data indicates that Pd and Pt were derived from oxidized alkaline magmas generated by the partial melting of an enriched mantle source. 展开更多
关键词 PORPHYRY SKARN copper-molybdenum palladium PLATINUM GOLD FENGSHAN China
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