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Neutrophil-mimicking therapeutic nanoparticles for targeted chemotherapy of pancreatic carcinoma 被引量:14
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作者 Xi Cao Ying Hu +5 位作者 Shi Luo Yuejing Wang Tao Gong Xun Sun Yao fun Zhirong Zhang 《Acta Pharmaceutica Sinica B》 SCIE CSCD 2019年第3期575-589,共15页
Due to the critical correlation between inflammation and carcinogenesis, a therapeutic candidate with anti-inflammatory activity may find application in cancer therapy. Here, we report the therapeutic efficacy of cela... Due to the critical correlation between inflammation and carcinogenesis, a therapeutic candidate with anti-inflammatory activity may find application in cancer therapy. Here, we report the therapeutic efficacy of celastrol as a promising candidate compound for treatment of pancreatic carcinoma via na?ve neutrophil membrane-coated poly(ethylene glycol) methyl ether-block-poly(lactic-co-glycolic acid)(PEG-PLGA) nanoparticles. Neutrophil membranecoated nanoparticles(NNPs) are well demonstrated to overcome the blood pancreas barrier to achieve pancreas-specific drug delivery in vivo. Using tumor-bearing mice xenograft model, NNPs showed selective accumulations at the tumor site following systemic administration as compared to nanoparticles without neutrophil membrane coating. In both orthotopic and ectopic tumor models,celastrol-loaded NNPs demonstrated greatly enhanced tumor inhibition which significantly prolonged the survival of tumor bearing mice and minimizing liver metastases. Overall, these results suggest that celastrol-loaded NNPs represent a viable and effective treatment option for pancreatic carcinoma. 展开更多
关键词 Na■ve neutrophils membrane CELASTROL PEG-PLGA nanoparticle Pancreatic carcinoma Inflammation
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间苯二甲酸连接的氢键导致的二维锌配位聚合物的合成及晶体结构 被引量:6
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作者 李彬 孙跃飞 +3 位作者 苟少华 姚景才 Suchada Chantrapromma Hoong-Kun fun 《无机化学学报》 SCIE CAS CSCD 北大核心 2001年第6期917-920,共4页
A H-bond induced two-dimensional in finite coordination polymer[Zn(1,3-BDC)(Im)2]n·2nCH3 OH(1,3-BDC =1,3-benzenedicarboxylate,Im =imidazole)was synthesized and crystallo-graphically determined by X-ray dif fracti... A H-bond induced two-dimensional in finite coordination polymer[Zn(1,3-BDC)(Im)2]n·2nCH3 OH(1,3-BDC =1,3-benzenedicarboxylate,Im =imidazole)was synthesized and crystallo-graphically determined by X-ray dif fraction.The crystal structure belongs to monoclinic system with space group C2/c.a=23.1836(2),b=10.1905(1),c=17.0118(2)?,β=115.099°,V=3639.58(6)?3,D=1.499g·cm-3,Z =8,F000=1688,μ=1.384mm-1,R1=0.0715,wR2=0.1645.Each Zn?ion is four-coordinated with a geome try of distorted tetrahedron.Each 1,3-BDC acts as a bridge to bond two neighboring zinc ions,leading to an infinite o ne-dimensional chainlike coordination polymer.Each chain wa s linked by hydrogen bonds with its neighbors to form a two-dimensional net. 展开更多
关键词 锌(Ⅱ)配合物 氢键 晶体结构 二维配位聚合物 合成 晶体结构 间苯二甲酸
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两种新型吡啶盐的合成,表征及双光子性质研究 被引量:4
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作者 周虹屏 郝扶影 +5 位作者 张居舟 赵祖志 李东梅 吴杰颖 田玉鹏 Hoong-Kun fun 《无机化学学报》 SCIE CAS CSCD 北大核心 2004年第10期1165-1171,共7页
本文报道了两种新的吡啶盐的合成,用元素分析、红外光谱、单晶X-射线衍射进行了表征。研究了它们的紫外光谱、荧光光谱和光限幅特性,发现它们的DMF溶液对1064nm皮秒脉冲激光表现出明显的光限幅特性。
关键词 吡啶盐 合成 双光子性质 元素分析 红外光谱 单晶X-射线衍射 光限幅特性
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簇合物[WS_4Ag_3(PPh_3)_3{S_2P(OCH_2Ph)_2}]的合成、晶体结构及非线性光学性质 被引量:1
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作者 常青 王燕 +5 位作者 李小华 宋瑛林 郑和根 忻新泉 S. Shanmuga Sundara Raj Hoong-Kun fun 《无机化学学报》 SCIE CAS CSCD 北大核心 2003年第6期574-578,共5页
本文用(NH4)2WS4,Ag犤S2P(OCH2Ph)2犦和PPh3为原料合成了簇合物犤WS4Ag3(PPh3)3狖S2P(OCH2Ph)2狚犦,并得到了晶体。晶体属正交晶系,空间群为P212121,晶胞参数a=1.32370(4)nm,b=1.34427(4)nm,c=3.83246(11)nm。X-射线单晶结构测定结果表... 本文用(NH4)2WS4,Ag犤S2P(OCH2Ph)2犦和PPh3为原料合成了簇合物犤WS4Ag3(PPh3)3狖S2P(OCH2Ph)2狚犦,并得到了晶体。晶体属正交晶系,空间群为P212121,晶胞参数a=1.32370(4)nm,b=1.34427(4)nm,c=3.83246(11)nm。X-射线单晶结构测定结果表明它具有巢状分子结构,配体(PhCH2O)2PS2-(简称dtp)的两个S原子中的一个硫原子仅与一个金属原子配位,另一个硫原子则同时与两个金属原子配位。簇合物的非线性光学性质用脉宽8ns激光在532nm波长进行了研究。该化合物表现为一定的光学吸收和强的自聚焦效应,其三阶非线性吸收系数α2=1.50×10-10m·W-1,折射系数n2=2.45×10-11esu。 展开更多
关键词 原子簇合物 [WS4Ag3(PPh3)3{S2P(OCH2Ph)2}] 合成 晶体结构 非线性光学性质 银(I)配合物
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Surgical outcomes for unilateral superior oblique palsy in Chinese population: a retrospective study 被引量:4
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作者 Gordon Shing Kin Yau Victor Tak Yau Tam +2 位作者 Jacky Wai Yip Lee Theo Tak Kwong Chan Can Yin fun Yuen 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2015年第1期107-112,共6页
AIM: To evaluate the outcome after surgery for unilateral superior oblique(SO) palsy in Chinese.METHODS: The medical records of 39 patients that underwent surgery for unilateral SO palsy between January 2003 and Decem... AIM: To evaluate the outcome after surgery for unilateral superior oblique(SO) palsy in Chinese.METHODS: The medical records of 39 patients that underwent surgery for unilateral SO palsy between January 2003 and December 2012 at Caritas Medical Centre, Hong Kong, were retrospectively reviewed. All surgeries were performed by a single surgeon. Pre-operative assessments for vertical deviation, cyclo-deviation, and Knapp’s classification were obtained to determine the nature and degree of surgical correction.Vertical deviation was measured at 1wk; 1, 6mo and on last follow-up day post-operatively. Cyclo-deviation was measured on last follow-up day post-operatively.RESULTS: During the 10 y period, 39 subjects were recruited. The most common etiology was congenital(94.9%). Knapp’s Type III(66.7%) and Type I(12.8%)classifications were the most common subtypes. To treat SO palsy, the most common surgical procedures were:isolated inferior oblique(IO) anteriorization(41.0%),isolated IO myectomy(10.3%), and isolated IO recession(10.3%). At 3.5 ±2.1y post-operatively, the vertical deviation was significantly reduced(15.1 ±6.2 PD versus0.5±1.4 PD, P 【0.0001) without significant improvement in cyclo-deviation(P =0.5). Initial vertical deviation was correlated with cyclo-torsion(r =0.4, P =0.007). Those with over-correction had greater initial vertical deviation(19.4±7.2 PD versus 13.2±4.3 PD, P =0.003). After a single operation, 84.6% of subjects achieved a vertical deviation within ±3 PD.· CONCLUSION: The majority of subjects achieved corrected vertical deviation after a single surgery although there was no improvement in cyclo-deviation.Those with over-correction of primary position deviation had greater preoperative vertical deviation and it may be related to simultaneous multiple muscle surgery. 展开更多
关键词 superior oblique palsy vertical deviation SURGERY DIPLOPIA
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Diabetic muscle infarction in end-stage renal disease: A scoping review on epidemiology, diagnosis and treatment 被引量:4
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作者 Tuck Yean Yong Kareeann Sok fun Khow 《World Journal of Nephrology》 2018年第2期58-64,共7页
Diabetic muscle infarction(DMI) refers to spontaneous ischemic necrosis of skeletal muscle among people with diabetes mellitus, unrelated to arterial occlusion. People with DMI may have coexisting end-stage renal dise... Diabetic muscle infarction(DMI) refers to spontaneous ischemic necrosis of skeletal muscle among people with diabetes mellitus, unrelated to arterial occlusion. People with DMI may have coexisting end-stage renal disease(ESRD) but little is known about its epidemiology and clinical outcomes in this setting. This scoping review seeks to investigate the characteristics, clinical features, diagnostic evaluation, management and outcomes of DMI among people with ESRD. Electronic database (Pub Med/MEDLINE, CINAHL, SCOPUS and and EMBASE) searches were conducted for ("diabetic muscle infarction" or "diabetic myonecrosis") and("chronic kidney disease" or "renal impairment" or "dialysis" or "renal replacement therapy" or "kidney transplant ") from January 1980 to June 2017. Relevant cases from reviewed bibliographies in reports retrieved were also included. Data were extracted in a standardized form. A total of 24 publications with 41 patients who have ESRD were included. The mean age at the time of presentation with DMI was 44.2 years. Type 2 diabetes was present in 53.7% of patients while type 1 in 41.5%. In this cohort, 60.1% were receiving hemodialysis, 21% on peritoneal dialysis and 12.2% had kidney transplantation. The proximal lower limb musculature was the most commonly affected site. Muscle pain and swelling were the most frequent manifestation on presentation. Magnetic resonance imaging (MRI) provided the most specific findings for DMI. Laboratory investigation findings are usually non-specific. Non-surgical therapy is usually used in the management of DMI. Short-term prognosis of DMI is good but recurrence occurred in 43.9%. DMI is an uncommon complication in patients with diabetes mellitus, including those affected by ESRD. In comparison with unselected patients with DMI, the characteristics and outcomes of those with ESRD are generally similar. DMI may also occur inkidney transplant recipients, including pancreas-kidney transplantation. MRI is the most useful diagnostic investigation. Non-surgical treatment in 展开更多
关键词 DIABETIC muscle INFARCTION DIALYSIS END-STAGE RENAL disease Kidney TRANSPLANT RENAL replacement therapy
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左室流出道速度时间积分变化率预测脓毒症患者容量反应性的准确性 被引量:4
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作者 解进 万静洁 +4 位作者 徐丽 陈青 张玉坤 陈军 詹英 《中华麻醉学杂志》 CAS CSCD 北大核心 2018年第5期591-594,共4页
目的评价左室流出道速度时间积分变化率(△VTI)预测脓毒症患者容量反应性的准确性。方法脓毒症或脓毒症休克接受机械通气治疗的患者20例,年龄≥18岁,呼吸机通气模式均为SIMV+VC。采用超声测量左室流出道VTI、SV和CO。先经1min静脉... 目的评价左室流出道速度时间积分变化率(△VTI)预测脓毒症患者容量反应性的准确性。方法脓毒症或脓毒症休克接受机械通气治疗的患者20例,年龄≥18岁,呼吸机通气模式均为SIMV+VC。采用超声测量左室流出道VTI、SV和CO。先经1min静脉输注钠钾镁钙葡萄糖注射液100ml并在1min内完成超声测定,而后经14min静脉输注钠钾镁钙葡萄糖注射液400ml。容量反应性定义为输注晶体液500ml后SV或CO增加〉15%,并以此将患者分为有反应组和无反应组。计算补液100ml后AVTI、△SV和△CO。采用受试者工作特征曲线评估△VTI、ASV和/△CO预测患者容量反应性的准确性。结果AVTI、ASV、ACO预测患者容量反应性的曲线下面积分别为0.95、0.91、0.88;以AVTI≥10%为临界点,预测容量反应性的敏感度为90%,特异度为80%。结论△VTI可准确预测脓毒症患者的容量反应性。 展开更多
关键词 血流速度 脓毒症 血管容量
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Avian influenza virus directly infects human natural killer cells and inhibits cell activity 被引量:4
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作者 Huawei Mao Yinping Liu +3 位作者 Sin fun Sia JS Malik Peiris Yu-Lung Lau Wenwei Tu 《Virologica Sinica》 SCIE CAS CSCD 2017年第2期122-129,共8页
Natural killer (NK) cell is a key component of innate immunity and plays an important role in host defense against virus infection by directly destroying infected cells. Influenza is a respiratory disease transmitte... Natural killer (NK) cell is a key component of innate immunity and plays an important role in host defense against virus infection by directly destroying infected cells. Influenza is a respiratory disease transmitted in the early phase of virus infection. Evasion of host innate immunity including NK cells is critical for the virus to expand and establish a successful acute infection. Previously, we showed that human influenza HIN1 virus infects NK cells and induces cell apoptosis, as well as inhibits NK cell activity. In this study, we further demonstrated that avian influenza virus also directly targeted NK cells as an immunoevasion strategy. The avian virus infected human NK cells and induced cell apoptosis. In addition, avian influenza virion and HA protein inhibited NK cell cytotoxicity. This novel strategy has obvious advantages for avian influenza virus, allowing the virus sufficient time to expand and subsequent spread before the onset of the specific immune response. Our findings provide an important clue for the immunopathogenesis of avian influenza, and also suggest that direct targeting NK cells may be a common strategy used by both human and avian influenza viruses to evade NK cell immunity. 展开更多
关键词 natural killer (NK) cell avian influenza virus (AIV) IMMUNOEVASION directioninfection INHIBITION CYTOTOXICITY
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配位聚合物[HgI_2(bpea)]_n[bpea=1,2-双(4-吡啶基)乙烷]的合成结构表征和光学折射效应(英文) 被引量:2
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作者 牛云垠 宋瑛林 +3 位作者 侯红卫 郑和根 fun Hoong -Kun 忻新泉 《无机化学学报》 SCIE CAS CSCD 北大核心 2001年第5期723-729,共7页
制备44连吡啶基二卤加和物MX244′bipyn仍然有较大困难。这类化合物数量不多且已报道的多为难处理的微晶材料。本文在室温下通过简单的操作合成了新的碘化汞连吡啶乙烷加和物HgI2bpean。X射线单晶衍射分析表明其中的汞原子通过与两个碘... 制备44连吡啶基二卤加和物MX244′bipyn仍然有较大困难。这类化合物数量不多且已报道的多为难处理的微晶材料。本文在室温下通过简单的操作合成了新的碘化汞连吡啶乙烷加和物HgI2bpean。X射线单晶衍射分析表明其中的汞原子通过与两个碘原子以及吡啶乙烷的两个氮原子配位形成扭曲的四面体构型。每个HgI2单元由bpea桥连形成锯齿状链。其非线性光学性质用8纳秒激光在532nm波长进行了研究。该化合物相对于入射光表现为一定的光学吸收和强的自聚焦效应,其三阶非线性吸收系数α2=1.1×10-11m·W-1折射系数n2=5.29×10-18m2·W-1。 展开更多
关键词 碘化汞连吡啶乙烷加和物 光学折射效应 合成 配位聚合物 汞加和物 非线性光学性质 锯齿状结构 [HgI2(bpea)]n 1 2-双(4-吡啶基)乙烷
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一种具有双光子活性的新型吡啶盐的合成、表征及性质 被引量:4
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作者 周虹屏 郝扶影 +5 位作者 张居舟 赵祖志 李东梅 吴杰颖 田玉鹏 Hoong-Kun fun 《应用化学》 CAS CSCD 北大核心 2005年第6期610-614,共5页
合成了1种新的DπA结构的吡啶盐,通过红外、元素分析、热重分析、单晶X射线衍射对化合物的结构进行了表征。研究了它的荧光光谱,用1064nm皮秒脉冲激光研究了它的三阶非线性光学特性。结果表明,该吡啶盐的双光子吸收系数β=0.1047cm/GW,... 合成了1种新的DπA结构的吡啶盐,通过红外、元素分析、热重分析、单晶X射线衍射对化合物的结构进行了表征。研究了它的荧光光谱,用1064nm皮秒脉冲激光研究了它的三阶非线性光学特性。结果表明,该吡啶盐的双光子吸收系数β=0.1047cm/GW,双光子吸收截面σ=3.2473×10-46cm4·s·photon-1,当泵浦能量达到1.677mJ时,上转换效率达到1.9%。 展开更多
关键词 D-π-A吡啶盐 三阶非线性光学特性 单晶X射线衍射 Z扫描
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Synthesis, Characterization and Two-Photon Absorption Properties of a Novel Pyridinium Salt 被引量:1
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作者 郝扶影 施鹏飞 +9 位作者 刘会军 吴杰颖 杨家祥 田玉鹏 周广勇 蒋民华 fun Hoong Kun SUCHADA Chantraprommae 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2004年第4期354-359,共6页
A novel pyridinium salt, 2,4-bis[p-(N,N-dimethylamino)styryl]-N-methyl pyridinium iodide (BMSPI) was syn-thesized and characterized by TG, 1H NMR spectroscopy and elemental analysis, and the reaction process was studi... A novel pyridinium salt, 2,4-bis[p-(N,N-dimethylamino)styryl]-N-methyl pyridinium iodide (BMSPI) was syn-thesized and characterized by TG, 1H NMR spectroscopy and elemental analysis, and the reaction process was studied by using ES-MS. When BMSPI was pumped by a pulsed 1064 nm, 50 ps laser beam, it manifests highly ef-ficient TPA (Two-Photon Absorption) and up-conversion superradiance. The up-conversion efficiency was 6.0% at the pump energy of 4—6 mJ and the lifetime of two-photon fluorescence was measured as 59 ps. 展开更多
关键词 pyridinium salt two-photon induced fluorescence reaction mechanism
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丙二腈类化合物的室温固相合成、结构及单双光子荧光性质 被引量:2
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作者 马文 张胜义 +2 位作者 吴杰颖 田玉鹏 fun Hoong-Kun 《应用化学》 CAS CSCD 北大核心 2003年第9期862-866,共5页
固相反应合成了新型丙二腈类化合物。反应 0 5h完成 ,产率高达 93%以上。采用IR、UV、1HNMR及元素分析对产物进行了表征 ,并通过单晶X射线衍射确定了其中 1种化合物的结构。研究表明 ,产物具有单光子和双光子吸收荧光效应 ,并表现出类... 固相反应合成了新型丙二腈类化合物。反应 0 5h完成 ,产率高达 93%以上。采用IR、UV、1HNMR及元素分析对产物进行了表征 ,并通过单晶X射线衍射确定了其中 1种化合物的结构。研究表明 ,产物具有单光子和双光子吸收荧光效应 ,并表现出类似的溶剂效应。 展开更多
关键词 丙二腈类化合物 室温固相反应 双光子荧光
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Comprehensive Analysis of Lipid Composition in Crude Palm Oil Using Multiple Lipidomic Approaches 被引量:2
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作者 Wei fun Cheong Markus R.Wenk Guanghou Shui 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2014年第5期293-304,共12页
Palm oil is currently the leading edible oil consumed worldwide. Triacylglycerol (TAG) and diacylglycerol (DAG) are the dominant lipid classes in palm oil. Other lipid classes present in crude palm oil, such as ph... Palm oil is currently the leading edible oil consumed worldwide. Triacylglycerol (TAG) and diacylglycerol (DAG) are the dominant lipid classes in palm oil. Other lipid classes present in crude palm oil, such as phospholipids and galactolipids, are very low in abundance. These low-abundance lipids constitute key intermediates in lipid biosynthesis. In this study, we applied multiple lipidomic approaches, including high-sensitivity and high-specificity multiple reaction monitoring, to comprehensively quantify individual lipid species in crude palm oil. We also established a new liquid chromatography-coupled mass spectrometry method that allows direct quantification of low-abundance galactolipids in palm oil without the need for sample pretreatrnent. As crude palm oil contains large amounts of neutral lipids, our direct-detection method circumvents many of the challenges encountered with conventional lipid quantification methods. This approach allows direct measurement of lipids with no hassle during sample preparation and is more accurate and precise compared with other methods. 展开更多
关键词 Palm oil Mass spectrometry LIPIDOMICS GALACTOLIPIDS PHOSPHOLIPIDS
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硫代碳酰肼缩邻香草醛的合成、晶体结构及非线性光学性质的研究 被引量:2
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作者 周虹屏 李东梅 +8 位作者 卜继琴 金凤 朱永敏 张居舟 吴际 吴杰颖 田玉鹏 Suchada Chantrapromma fun Hoong-Kun 《化学世界》 CAS CSCD 北大核心 2006年第2期94-98,共5页
报道合成了一种新的化合物硫代碳酰肼缩邻香草醛(1)(C19H22N5O4S,Mr=416.48),通过元素分析、红外光谱、紫外光谱和氢核磁共振谱对其结构进行了表征。用X-射线单晶衍射测定了其晶体结构。结果表明:晶体属于三斜晶系,P1-空间群,晶胞参数:a... 报道合成了一种新的化合物硫代碳酰肼缩邻香草醛(1)(C19H22N5O4S,Mr=416.48),通过元素分析、红外光谱、紫外光谱和氢核磁共振谱对其结构进行了表征。用X-射线单晶衍射测定了其晶体结构。结果表明:晶体属于三斜晶系,P1-空间群,晶胞参数:a=0.9983(1)nm,b=1.0509(1)nm,c=1.0748(1)nm,α=90.089(2)°,β=110.033(2)°,γ=103.069(2)°。用开孔Z-扫描技术在523 nm脉冲激光波长下研究了该化合物的DMF溶液的三阶非线性光学性质。单晶数据注册编号:CCDC 240088。 展开更多
关键词 硫代碳酰肼缩邻香草醛 X-射线单晶衍射 Z-扫描
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[Mg(H-Sulf)(H_2O)_5](H-Sulf)·5H_2O的合成、晶体结构和谱学表征 被引量:2
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作者 康澍 陈振锋 +3 位作者 梁宇宁 李冬青 梁宏 fun Hoong-kun 《广西师范大学学报(自然科学版)》 CAS 北大核心 2006年第3期68-72,共5页
柳氮磺胺吡啶(H3-Su lf)与氢氧化镁反应得到化合物[M g(H-Su lf)(H2O)5](H-Su lf).5H2O。用元素分析、U v-V is、荧光、IR光谱和单晶X-射线衍射方法对该化合物进行表征。化合物的化学式:C36H46M gN8O20S2,M r=999.24,三斜晶系,P-1空间群... 柳氮磺胺吡啶(H3-Su lf)与氢氧化镁反应得到化合物[M g(H-Su lf)(H2O)5](H-Su lf).5H2O。用元素分析、U v-V is、荧光、IR光谱和单晶X-射线衍射方法对该化合物进行表征。化合物的化学式:C36H46M gN8O20S2,M r=999.24,三斜晶系,P-1空间群,晶胞参数:a=1.115 16(13)nm,b=1.544 71(19)nm,c=1.604 71(19)nm,=α115.654(2),°β=107.909(2),°γ=91.861(2),°V=2.326 4(5)nm3,Z=2,Dc=1.426 M g/m3,R 1=0.130,wR 2=0.259(I>2σ(I)),S=1.048。化合物为离子型化合物,由阳离子[M g(H-Su lf)(H2O)5]+,阴离子[H-Su lf]-和5个结晶水组成。其中心金属M g(Ⅱ)离子采取六配位变形的八面体几何构型,周围被5个H2O和1个来自柳氮磺胺吡啶的单齿配位的羧基O所包围,羟基和吡啶N均未参与配位。化合物通过复杂的分子内和分子间氢键作用形成三维的超分子结构。 展开更多
关键词 合成 晶体结构 柳氮磺胺吡啶 镁(Ⅱ)配合物
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Optimizing the Asset and Liability Management of Telecommunication Company using Goal Programming Model 被引量:1
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作者 Lam Weng Siew Lam Weng Hoe Lee Pei fun 《Journal of Electronic & Information Systems》 2020年第2期24-29,共6页
Since the telecommunications companies experience great competition,high churn rate,data traffic issues during the Covid-19 pandemic and the upgrade to 5G connectivity,the finance management of a telecommunications co... Since the telecommunications companies experience great competition,high churn rate,data traffic issues during the Covid-19 pandemic and the upgrade to 5G connectivity,the finance management of a telecommunications company should be analyzed to study the volatility and returns in the sector.This paper aims to develop a goal programming model to examine the asset and liability management of a telecommunication company,namely Telekom Malaysia Berhad(TM)in Malaysia.The result of this study shows that TM has achieved all the goals in maximizing assets,equities,profits,earnings and optimum management item while minimizing liabilities over the period of study from 2015 to 2019.Potential improvements on these goals have also been identified through this study.This paper has also contributed to the studies in financial management since past studies have not been done on asset and liability management in telecommunications companies which is rapidly growing and expanding even while the world is suffering from economy crisis during this pandemic. 展开更多
关键词 Goal programming Optimal solution TELECOMMUNICATION Potential improvement
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吡啶酰胺在Cd(Ⅱ)存在下的醇解反应及结构表征(英文)
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作者 张俊勇 涂超 +4 位作者 林骏 Hoong-Kun fun Suchad Chantrapromma 游效曾 郭子建 《无机化学学报》 SCIE CAS CSCD 北大核心 2002年第6期554-558,共5页
X-射线晶体结构分析表明,在90℃的水热条件下,N-(8-喹啉基)吡啶-3-酰胺在Cd的存在下发生醇解。醇解产物为8-氨基喹啉(HL1)和吡啶-3-羧乙酯(HL2),它们与Cd?配位形成四方锥型化合物。该配合物为单斜晶系,空间群P21/c,a=18.1089(1)?,b=8.99... X-射线晶体结构分析表明,在90℃的水热条件下,N-(8-喹啉基)吡啶-3-酰胺在Cd的存在下发生醇解。醇解产物为8-氨基喹啉(HL1)和吡啶-3-羧乙酯(HL2),它们与Cd?配位形成四方锥型化合物。该配合物为单斜晶系,空间群P21/c,a=18.1089(1)?,b=8.9986(1)?,c=19.3070(2)?,β=113.085(1)和Z=4。 展开更多
关键词 吡啶酰胺 Cd(Ⅱ) 醇解反应 结构表征 水热合成 镉(Ⅱ)
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层状配位聚合物犤Pb(NCS)_2(bpea)_n的合成,结构和非线性光学性质(bpea=1,2-双(4-吡啶基)乙烷)(英文)
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作者 牛云垠 侯红卫 +4 位作者 李峰 郑和根 宋瑛林 fun Hoong-Kun 忻新泉 《无机化学学报》 SCIE CAS CSCD 北大核心 2001年第4期533-537,共5页
室温下Pb(OAC)2·3H2O,KNCS,和1,2-双(4-吡啶基)乙烷在甲醇中反应生成了八员环支撑的层状配位聚合物犤Pb(NCS)2(bpea)犦n。三阶非线性Z-扫描研究表明该化合物具有非线性折射行为:其非线性吸收系数α2=1.1×10-11m·W-1,非... 室温下Pb(OAC)2·3H2O,KNCS,和1,2-双(4-吡啶基)乙烷在甲醇中反应生成了八员环支撑的层状配位聚合物犤Pb(NCS)2(bpea)犦n。三阶非线性Z-扫描研究表明该化合物具有非线性折射行为:其非线性吸收系数α2=1.1×10-11m·W-1,非线性折射系数n2=6.055×10-18m2·W-1。 展开更多
关键词 层状配位聚合物 铅加合物 1 2-双(4-吡啶基)乙烷 非线性光学性质 Z-扫描 非线性折射系数
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具有梯形结构钴(Ⅱ)配位聚合物的合成及晶体结构(英文)
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作者 吴杰颖 潘月礼 +3 位作者 张宣军 张明亮 田玉鹏 fun Hoong-Kun 《无机化学学报》 SCIE CAS CSCD 北大核心 2003年第12期1347-1350,共4页
Co(NO3)2, N carbazolyacetic acid and 4,4′ bipyridyl can give rise to a novel coordination polymer [Co2(Cabo)2(NO3)2(4,4′ bipy)2]n using a fritted U tube. Single crystal X ray diffraction displays in the complex, eac... Co(NO3)2, N carbazolyacetic acid and 4,4′ bipyridyl can give rise to a novel coordination polymer [Co2(Cabo)2(NO3)2(4,4′ bipy)2]n using a fritted U tube. Single crystal X ray diffraction displays in the complex, each Co? is six coordinated by two N atoms from different 4,4′ bipyridyl ligands, two O atoms of the bridge from two N carbazolyacetic acid and two O atoms of one nitrate anion to form a distorted octahedral. Two O atoms of the carboxyl group act as bridge to link two Co? atoms. The resulting structure is a ladder polymer. CCDC: 211713. 展开更多
关键词 梯形分子结构 钴配位聚合物 合成 晶体结构 咔唑乙酸 4 4’-联吡啶
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Synthesis, Crystal Structure and Nonlinear Optical Properties of Nickel(Ⅱ) Complex with Schiff-base Ligand 被引量:1
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作者 薛照明 张宣军 +3 位作者 田玉鹏 吴杰颖 蒋民华 fun Hoong Kun 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2003年第3期265-269,共5页
The nickel(Ⅱ) complex with the new ligand of S-benzyl-b-N-[10-ethyl- phenothiazine-3-methylene]dithiocarbazate(HL) crystallizes in the triclinic system, space group P?with a = 7.516(1), b = 11.322(1), c = 13.366(1) ,... The nickel(Ⅱ) complex with the new ligand of S-benzyl-b-N-[10-ethyl- phenothiazine-3-methylene]dithiocarbazate(HL) crystallizes in the triclinic system, space group P?with a = 7.516(1), b = 11.322(1), c = 13.366(1) , a = 84.818(1), b = 81.688(1), g = 76.037(1), V = 1090.26(3) 3, Z = 1, Dc = 1.413 g/cm3, F(000) = 482, m(MoKa) = 0.774 mm-1 (l = 0.7103 ?, R = 0.0573 and wR = 0.1375 for 3357 observed reflections with I ≥ 2s(I). The HL has lost a proton from its tautomeric thiol form and acts as a single negatively charged bidentate ligand coordinating to the nickel ion via the mercapto sulfur and b-nitrogen atoms. The geometry around Ni(Ⅱ) is almost square-planar with two equivalent NiN and NiS bonds. The nonlinear absorption of HL and NiL2 solutions (in DMF) was measured by open-aperture Z-scan technique at the wavelength of 532 nm. 展开更多
关键词 crystal structure nickel complex NLO
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