关于Hessenberg 矩阵与Toeplitz 矩阵的相似

用解矩阵方程的方法直接证明 :对任一个单位上Hessenberg矩阵 H ,存在上Hessenberg的Toeplitz矩阵 T和单位上三角阵X ,使得XHX-1=T ,并且证明这样的T和X 都是唯一的国家自然科学基金( 19801029) 和福建省自然科学基金( F00023) 资助项

Synthesis of Ruthena-polycyclic Complexes by Ruthenium-Vinylcarbene Complex

研究了配位不饱和的钌杂S-顺丁二烯化合物[ru(CHC(PPH3)CH(2-Py))Cl2PPH3]bf4(1)与水、甲醇、苯胺和2-巯基吡啶等亲核试剂的[4+1]关环反应,合成了一系列有趣的钌杂多环化合物[ru(CHC(PPH3)CHr(2-Py))Cl(PPH3)2]bf4[r=OH(2),OME(3),和nHPH(4)]与[ru(CHC(PPH3)CH(S(2-Py))(2-Py))PPH3(S(2-Py)]bf4(5).此外,将配位不饱和的钌配合物1与三苯基膦配体反应,制备了类似于氮杂金属萘的配位饱和化合物[ru(CHC(PPH3)CH(2-Py))Cl2(PPH3)2]bf4(6).6与Hbf4反应可生成金属杂环结构类似的分子内含三氯桥的双钌核配合物[{ru(CHC(PPH3)CH(2-Py))PPH3}2(μ-Cl)3](bf4)3(7).以上产物均通过核磁(nMr)与元素分析进行了表征,并解析了部分产物的X射线单晶结构.Treatment of ruthenium-vinylcarbene complex [Ru(CHC(PPh3)CH(2-Py))Cl2 PPh3 ]BF4(1) and PPh3 with nucleophilic reagents H2 O,CH3 OH,NH2 Ph,or 2-mercaptopyridine led to the ruthena-polycyclic complexes [Ru(CHC(PPh3)CHR(2-Py))Cl(PPh3)2 ]BF4 [R = OH(2),R = OCH3(3),R = NHPh(4)] or [Ru(CHC(PPh3)CH(S(2-Py))(2-Py))PPh3(S(2-Py)]BF4(5).They are stable under air at solid state.CH3 OH in the reaction is not only the reagent but also the solvent and the reaction must be heated at 60 ℃ for 6 h.All the other reactions were carried out at room temperature in CH2Cl2.The crystals of 4 and 5 were grown from CH2 Cl2 and CHCl3 solutions layered with diethyl ether,respectively.The structures 4 and 5 were determined by X-ray crystallography.The crystal size of 4 is a=1.29145(3) nm,b=1.37687(5) nm,c= 1.86914(4) nm,α=92.114(2)°,β=106.271(2)°,γ=96.333(3)° and the size of 5 is a=1.15333(18) nm,b=1.20072(19) nm,c=1.9081(3) nm,α=88.466(3)°,β=87.918(3)°,γ=79.521(3)°.In addition,refluxing 1 with PPh3 in CHCl3 for 6 h to produce red solid [Ru(CHC(PPh3)CH(2-Py))Cl2(PPh3)2 ]BF4(6).The reaction of complex 6 with HBF4 at room temperature for 3 h afforded the(μ-Cl)3-bridged bisruthenium-vinylcarbene complex [{Ru(CHC(PPh3)CH(2-Py))PPh3 }2(μ-Cl)3 ](BF4)3(7) in 87% yield.The crystal of 6 was grown from CH3 COCH3 solution layered with diethyl ether,and the crystal of 7 was grown from CHCl3 solution layered with diethyl ether.The structures of 6 and 7 were also determined by X-ray crystallography.The crystal size of 6 and 7 are a=1.13777(3) nm,b=1.56466(7) nm,c=1.79541(7) nm,α=75.822(3)°,β=79.502(2)°,γ= 79.259(3)°,a=1.68830(3) nm,b=2.33421(4) nm,c=2.48603(4) nm,α=90°,β=96.5530(10)°,γ=90°,respectively.The CCDC number for 3,5,6,and 7 are 945539(3),945538(5),945541(6),and 945542(7).All these complexes were fully characterized by elemental analysis and NMR spectroscopy.国家重点基础研究发展计划(No.2012CB821600); 国家自然科学基金(Nos.20925208;21174115;21272193); 长江学者和创新团队发展计划资助~

1978～2008年中国湿地类型变化

分别基于美国陆地卫星(Landsat MSS/TM/ETM+)和中巴资源卫星(CBERS-02B)影像数据,以人工目视解译为主,完成了中国1978～2008年4期(基准年分别为1978,1990,2000和2008年)湿地遥感制图,并进行了大量的室内外验证.在此基础上,对我国湿地现状及近30年来湿地变化进行了初步分析,得到以下主要结论:(ⅰ)截止2008年,中国湿地面积约为324097km2,其中以内陆沼泽(35%)和湖泊湿地(26%)为主.(ⅱ)1978～2008年,中国湿地面积减少了约33%,而人工湿地增加了约122%.过去30年里湿地减少的速度大幅降低,由最初5523km2/a(1978～1990年)降为831km2/a(2000～2008年).(ⅲ)减少的自然湿地(包括滨海湿地和内陆湿地),其类型变化由湿地向非湿地转化的比例逐渐降低.初期(1978～1990年)几乎全部(98%)转换为非湿地;在1990～2000年间减少的自然湿地约有86%转化为非湿地,而在2000～2008年,这一比例下降为77%.(ⅳ)气候变化和农业活动是中国湿地变化的主要驱动因素,湿地变化在中国分为三大不同特征区域,即西部三省/自治区(西藏、新疆和青海)、北部两省/自治区(黑龙江和内蒙古)和其他省市区.其中西部区域尤其是青藏高原,湿地变化的驱动因子以气候增温为主;新疆湿地由于气候增温和农业活动共同作用造成变化不大.北部省/自治区的湿地变化则主要由农业活动引起;而其他省市区的湿地变化几乎完全受控于人类的农业经济活动

On Similarity of Hessenberg Matrix and Toeplizt Matrix

用解矩阵方程的方法直接证明 :对任一个单位上Hessenberg矩阵 H ,存在上Hessenberg的Toeplitz矩阵 T和单位上三角阵X ,使得XHX-1=T ,并且证明这样的T和X 都是唯一的For any n×n complex unit upper Hessenberg matrix H, there exist a unique unit triangular matrix X and a unique unit upper Hessenberg Toeplitz matrix T such that XHX -1=T. The proof is simple and constructive, by means of solving the matrix equation directly.国家自然科学基金 (1980 10 2 9);; 福建省自然科学基金 (F0 0 0 2 3)资助项

On Similarity of Hessenberg Mat rix and Toeplizt Mat rix

摘要: 用解矩阵方程的方法直接证明:对任一个单位上Hessenberg 矩阵H ,存在上Hessenberg 的Toeplitz 矩阵T 和 单位上三角阵X ,使得XHX - 1 = T ,并且证明这样的T 和X 都是唯一的. Abstract : For any n ×n complex unit upper Hessenberg mat rix H , there exist a unique unit t riangular mat rix X and a unique unit upper Hessenberg Toeplitz mat rix T such that X HX - 1 = T . The proof is simple and con2 st ructive , by means of solving the mat rix equation directly.国家自然科学基金(19801029) 和福建省自然科学基金(F00023) 资助项

Epoxidation of Propylene over Ag/MgO Catalysts Modified Na~+ and Halogen Anions

通讯作者: [email protected][中文摘要]制备了一系列未经修饰和经Na+和卤素修饰的5%(质量分数)Ag/MgO催化剂.考察了富氧条件(p(C3H6)∶p(O2)=2.53∶98.8)下,Na+和卤素的修饰对Ag/MgO催化剂的丙烯环氧化反应性能的影响.研究发现,添加于催化剂中的Na+有助于环氧丙烷选择性的提高,而与Na+共存的Cl-和Br-则显著增加环氧丙烷的选择性.氧程序升温脱附(O2-TPD)表征显示,Ag/MgO催化剂中Na+和Cl-的添加提高了催化剂中次表面氧的含量和稳定性,从而促进了其在丙烯环氧化反应中的催化性能. [英文摘要]A series of 5%(by mass)Ag/MgO catalysts modified with and without Na+ and halogen anions were prepared,and the performances of these catalysts for epoxidation of propylene were studied under O2-rich condition(p(C3H6)∶p(O2)=2.53∶98.8) by using oxygen as oxidant.It was found that catalysts modified with Na+ showed higher selectivity for PO formation.Furthermore,Cl-or Br-coexisted with Na+ in the catalysts could also lead to obvious increase of PO selectivity(>20%).O2-TPD characterization suggested that Na+ and Cl- in the catalysts stabilized subsur face oxygen species Oβ , and this might favor the formation of PO.国家自然科学基金(20773099

Preparation and Identification of Micro-vesicles from Endothelial Membrane of Blood Brain Barrier of Sows

选二花脸母猪和长白母猪各 5头 ,取大脑皮质 ,制备微血管 ,分离内皮细胞微囊 ,应用倒置显微镜和透射电镜观察微囊的完整性 ;通过测定γ-谷氨酰转肽酶、5′-核苷酸酶、乙酰胆碱酯酶、乳酸脱氢酶、碱性磷酸酶等标志酶活性 ,鉴定微囊的纯度和生物学活性。结果表明 ,用该方法分离得到的大脑皮质内皮细胞微囊的完整性较好 ,纯度较高 ,生物学活性好 ,适合于对血脑屏障的转运研究The micro-vesicles were isolated and purified from the endothelial membrane of micro-vessels on cerebral cortex of 5 for each Erhualian and large white sows. The integrity of the vesicles was evaluated by inverted microscopy and electron microscopy. The purity and biological activity were determined by the activities of such enzymes as g-glutamy transpeptidase (g-GTase), 5′-nucleotidase (NTDase), acetylcholinesterase(ACSase), lactate dehydrogenase(LDHase) and alkaline phosphatase (AKPase). The results indicated that thd endothelial membrane vesicles isolated by the above-mentioned method is of high purity and biological activity and may be used to evaluate the transport via blood-brain barrier.国家自然科学基金资助项目 ( 3 9870 5 77

三峡水库湖北段沉积物磷形态及其分布特征

应用淡水沉积物的标准测试程序(SMT)测定了三峡水库湖北段长江干流和4条支流中14个采样点沉积物的总磷、无机磷、有机磷、铁/铝磷和钙磷的含量并对不同形态磷之间进行了相关性分析。结果表明,三峡水库湖北段水体表层沉积物中TP和各种磷的赋存形态存在明显的空间差异,TP含量为361.6~1 033.5 mg/kg;In-P是沉积物中磷的主要成分,占TP的58.1%~92.3%;沉积物中TP的增减主要来自In-P,In-P的增减主要来自Ca-P,Ca-P占In-P含量的53.7%~83.7%。而Org-P、Ca-P、Fe/Al-P三者的含量相对独立。长江湖北段一级支流在表层沉积物的TP空间分布特征总体表现为:香溪河>童庄河>袁水河>青干河。与其他支流相比,香溪河沉积物的总磷和各形态磷含量都显著高于其他支流。上述研究结果在一定程度上获得了不同形态磷在三峡水库湖北段的分布特征,为客观评价沉积物潜在的磷释放能力提供依据

Effect of Snow Melting Time on Individual Characteristics and Phenology of Fritillaria unibracteata

[目的]探讨融雪时间对川贝母生长和物候的影响。[方法]在青藏高原东部的一个高山雪床,在积雪早融部位与积雪晚融部位之间进行川贝母移植试验,观察川贝母的个体特征和物候的变化。[结果]川贝母的株高、单叶面积和地上生物量在早融与晚融部位之间有显著的差异,且晚融部位的值要大于早融部位的值;融雪时间对川贝母早期和中期物候阶段(如开始生长期、始花期)有影响,而对后期特别是晚期的物候阶段(如植株枯黄期)影响很小。[结论]积雪晚融的环境更有利于川贝母的生长,在人工种植中应遵循这一规律