Results 21 to 30 of about 1,490,657 (168)
World Water Policy, Volume 12, Issue 4, November 2026.ABSTRACT Biochemical oxygen demand (BOD) remains a core indicator of organic pollution in freshwater monitoring, but its role in water policy and practice is changing as water‐quality assessment moves toward predictive, integrative, and decision‐support approaches.
Isadora Favero Roque Cenci +5 more
wiley +1 more source
九配位多孔金属有机框架Eu（HCOO）3配合物的原位合成及其结构分析
四川大学学报. 自然科学版, 2014 在高温水热条件下,N,N-二甲基甲酰胺(DMF)水解生成甲酸配体,合成九配位的配合物Eu(HCOO)3,配合物通过红外光谱,X-射线单晶衍射和元素分析.结果显示:配合物为三方晶系,R3m空间群.a=1.04972(3)nm,b=1.04972(3)nm,c=0.40011(2)nm,α=90.00°,β=90.00°,γ=120.00°,V=0.38182(2)nm3.配合物中,甲酸根以三齿配位方式桥联,每1个铕(Ⅲ)离子与9个甲酸根的氧原子配位,形成了EuIII O9的九配位三帽三角棱柱体结构 ...
田婧, 薛智, 罗华锋
doaj
New Phytologist, Volume 252, Issue 1, Page 260-275, October 2026.Maize regeneration via somatic embryogenesis by ectopic expression of morphogenic factors TaGRF4‐TaGIF1 and ZmBBM. Summary Transformation is an indispensable tool for plant genetics and functional genomics. Although stable transformation in maize is no longer a major obstacle, there remains a need for accessible and efficient methods for academic ...
Zongliang Chen +8 more
wiley +1 more source
Zhejiang Daxue xuebao. Lixue ban, 2003 合成3种双核铂类配合物[{Pt(H2O)2I}μ—OOC—(CH2—)nCOO—{Pt(H2O)2I}](1~3)(n=0,1,2).用元素分析、摩尔电导、差热热重分析、红外光谱、紫外光谱和核磁共振氢谱等方法对其进行了表征.体外抗肿瘤活性表明,配合物1和3对多种人的肿瘤细胞有较高的活性,配合物2没有抗肿瘤活性.
ZHANGJin-chao(张金超) +6 more
doaj +1 more source
PLANTS, PEOPLE, PLANET, Volume 8, Issue 5, Page 1407-1418, September 2026.The jewel‐like flowers of Thismia are as rare as they are beautiful, often recorded from only a single site per species. Access to 15 populations of T. kobensis has enabled an uncommon, range‐wide assessment of morphology, genetics, and fungal partners. Our analyses showed that T.
Kenji Suetsugu +4 more
wiley +1 more source
两种长链吡啶类金属配合物催化PNPP和PNPA水解的动力学研究
四川大学学报. 自然科学版, 2002 用分光光度法研究了一种长链取代吡啶类配体 (L)及其铜 (II)和锌 (II)的配合物在2 5℃及 pH 6 .5～ 8.5的条件下 ,在CTAB胶束缓冲溶液中催化PNPP和PNPA水解的反应 .结果表明 ,活化的配体羟基可以作为反应过程中有效的亲核物种 ,锌 (II)配合物比铜 (II)配合物能更有效地催化PNPP的水解 ,这种情况可以解释为锌 (II)配合物中活化的配体羟基具有更强的亲核进攻能力 .作者推导了包括配体、金属离子和底物在内的金属配合物催化PNPP水解的三元复合物动力学模型 ...
杜娟, 曾宪诚, 李慎新
doaj
PLANTS, PEOPLE, PLANET, Volume 8, Issue 5, Page 1476-1499, September 2026.Biodiversity is threatened by human activities, with extinction debt accumulating rapidly. Many of these activities change the connectivity of populations, fragmenting existing population systems or bringing previously isolated populations or species into contact.
Zhiqin Long +7 more
wiley +1 more source
Brij35胶束溶液中大环Schiff碱配合物催化羧酸酯水解的动力学研究
四川大学学报. 自然科学版, 2004 作者研究了30℃时,Brij35胶束溶液中大环Schiff碱的Cu(Ⅱ)和Zn(Ⅱ)配合物催化PNPP和PNPA水解反应的动力学,结果表明,两种配合物催化PNPP和PNPA水解反应的机理是不同的.Cu(Ⅱ)配合物仅催化PNPP的水解,其机理是外部氢氧根离子对羰基的亲核进攻,而Zn(Ⅱ)配合物能同时加速PNPP和PNPA的水解,其机理为锌键合的氢氧根离子对PNPP羰基的分子内亲核进攻和锌键合的氢氧根离子对PNPA羰基的分子间亲核进攻.Zn(Ⅱ)配合物的催化活性高于Cu(Ⅱ)配合物.
韦一良, 覃治中, 程四清
doaj
PLANTS, PEOPLE, PLANET, Volume 8, Issue 5, Page 1563-1566, September 2026.Many plant species worldwide are struggling to regenerate due to the ongoing effects of climate change. These effects appear to be further exacerbated by the loss of keystone megafauna, which were important seed dispersers. By identifying the traits commonly seen in seeds spread by modern elephants, it is possible to predict which species likely ...
Andrew J. Tighe
wiley +1 more source
金属胶束催化VI:在Brij35胶束中Zn(II),Co(II)配合物对PNPP水解的催化作用
四川大学学报. 自然科学版, 2003 合成了3个配体:N,N,N′,N′, 四(2 羟乙基) 1,3 丙二胺(1),N,N,N′,N′, 四(2 羟乙基) 1,10 癸二胺(2),N,N,N′,N′, 四(2 羟乙基) 1,4 对甲苯二胺(3)及其与二价金属离子Zn(II)和Co(II)形成的金属配合物.在25℃,不同pH值下,研究了这些金属配合物在Brij35胶束溶液中催化PNPP水解的反应.其结果表明:在催化PNPP水解反应中,其活性物种为2∶1(配体:金属离子)的单核金属配合物 ...
蒋福宾 +5 more
doaj