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Crystal Structure Theory and Applications 2018年第1期7卷 1-18页

作者： Nana Odette Ngnabeuye Tayo Alain Djampouo Ndosiri Ndoye bridget Tanyi Rogers Fomuta Djimassingar Golngar Tagne Alain Charly Kuate Ngoune Jean Department of Chemistry University of Dschang Dschang Cameroon Department of Inorganic Chemistry University of Yaounde I Yaounde Cameroon Department of Chemistry Mongo Polytechnique University Institute (IUPM) Mongo Chad

The reaction of 2-ethylimidazole and zinc formate monohydrate in 1:2 ratio in toluene leads to the formation of bis(2-ethylimidazole)bis(formato)zinc(II)-water (1/1), [Zn(N2H8C5)2(OCHO)2]·H2O, 1 which has been characterized by several techniques, including elemental and thermal analyses, IR, 1HNMR and 13CNMR spectroscopies, single crystal X-ray diffraction and DFT studies. The results obtained show that this complex crystallizes in the orthorhombic crystal system of the Pbca space group, with cell parameters a = 14.7230(2) Å, b = 7.3880(10) Å, c = 29.0843(4) Å, α = 90°, β = 90°, γ = 90°, V = 3163.73 Å3 and Z = 8. The zinc center is bound to two molecules of 2-ethylimidazole, two formate molecules in a tetrahedral coordination geometry. One water of crystallization is present in the coordination sphere of the compound. Its molecular crystalline structure is strengthened by O/N-H…O, O-H…π, O-H…H, C-H…O, H…π, π…O and π…π interactions. The optimized structure, frontier molecular orbitals, global reactivity descriptors, molecular electrostatic potential, natural bond orbitals and the Mulliken atomic charges were investigated through theoretical studies.

关键词： Zinc Complex 2-Ethylimidazole Hydrogen Bonds Thermogravimetric Analysis 1HNMR 13CNMR X-Ray Theoretical Studies

美国高平原农业发展对地下水资源的影响及启示

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农业现代化研究 2016年第1期37卷 166-173页

作者：裴宏伟王彦芳沈彦俊马宏 bridget R.Scanlon 刘昌明中国科学院遗传与发育生物学研究所农业资源研究中心农业水资源重点实验室河北石家庄050021 河北省社会科学院河北省生态环境建设研究中心河北石家庄050051 河北建筑工程学院河北张家口075000 Bureau of Economic Geology Jackson School of Geosciences the University of Texas at Austin Austin Texas USA 78758 中国科学院大学北京100049

全球范围内的高强度灌溉农业已经造成了严重的地下水危机,威胁农业生态系统和经济社会的可持续运行。在中国北方农耕区,依靠地下水支撑的农业系统正面临严重的水资源问题,其中以华北平原最为严重。美国高平原在近60年中依靠消耗地下水... 详细信息

全球范围内的高强度灌溉农业已经造成了严重的地下水危机,威胁农业生态系统和经济社会的可持续运行。在中国北方农耕区,依靠地下水支撑的农业系统正面临严重的水资源问题,其中以华北平原最为严重。美国高平原在近60年中依靠消耗地下水支撑农业生产,小麦、玉米的生产总量分别增加了2倍和10倍,这些农业上的成就却以累积消耗地下水约3 360亿m3为代价,并降低了农业系统应对极端干旱事件的能力。1980年以后,高平原北部地区依靠良好的地下水补给条件并通过地下水的禁采限采、推广喷灌技术等措施降低了地下水的消耗速率。然而由于高平原中、南部地下水采补依然失衡而导致地下水资源持续减少;北部地区在地下水保护的同时却未能有效减少农田的氮肥施用水平,导致地下水浅埋区比较严重的地下水污染。因此,在当下华北平原及我国北方地下水灌溉区大力治理地下水超采问题的实践中,必须与农业面源污染的控制和治理相向而行、质量兼顾、综合统筹。

关键词：灌溉地下水超采地下水污染可持续发展华北平原

Synthesis, Characterization and DFT Studies of Two Zinc(II) Complexes Based on 2-Isopropylimidazole

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Open Journal of Inorganic Chemistry 2018年第4期8卷 105-124页

作者： Jean Jacques Anguile Odette Nana Ngnabeuye Ndosiri Ndoye bridget Tanyi Rogers Fomuta Alvine Loris Djoumbissie Alain Charly Kuate Tagne Jean Ngoune Department of Chemistry University of Sciences & Techniques of Masuku Franceville Gabon Department of Chemistry University of Dschang Dschang Cameroon Department of Inorganic Chemistry University of Yaounde 1 Yaounde Cameroon

Two novel coordination compounds, [Zn(L)2(OOCH)2] (1) and [Zn(L)3(OCHO)](OCHO)]·H2O (2) (where L = 2-isopropylimidazole, C6H10N2) have been prepared by reaction of 2-isopropylimidazole with zinc(II) formate at room temperature using toluene as solvent. These compounds were characterized by elemental and thermal analyses, IR, 1HNMR and 13CNMR spectroscopies, single crystal X-ray diffraction and DFT studies. The Zn centers in 1 and 2 adopt pseudo-tetrahedral coordination geometries. Compound 1 crystallizes in the monoclinic system P2/c space group whereas compound 2 crystallizes in the P-1 space group of the triclinic crystal system. Several types of hydrogen intra-/intermolecular interactions are observed in these materials and extend into a two-dimensional leaf like network in 1 and a two-dimensional lattice of rectilinear pillars in 2. Compounds 1 and 2 were also optimized and their frontier molecular orbitals, global reactivity descriptors, molecular electrostatic potential, natural bond orbitals were investigated using density functional theory (DFT). In fact the induced structural differences from complex 1 to complex 2 led to the reduction of the frontier molecular orbital energy gap by 1.338 eV and a decrease of the chemical hardness by 0.669 eV.

关键词： Zinc(II) Complexes of 2-Isopropylimidazole Thermogravimetric Analysis 1H-MR 13C-MR Crystal Structure DFT Studies

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用激光分光技术监测血液供氧水准

红外 1996年第3期17卷 42-43页

作者： bridget R.Marx 顾聚兴

对于胎儿和新生儿的诊断以及在临床护理中,需要用非侵入的技术监测大脑的供氧。英国Keele大学及其附属学院和英国伦敦大学中的一些研究小组正在研制基于激光的近红外分光技术,这种技术采用脉冲激光二极管和超速激光器,有朝一日,人们会... 详细信息

对于胎儿和新生儿的诊断以及在临床护理中,需要用非侵入的技术监测大脑的供氧。英国Keele大学及其附属学院和英国伦敦大学中的一些研究小组正在研制基于激光的近红外分光技术,这种技术采用脉冲激光二极管和超速激光器,有朝一日,人们会用这种技术来检查病人。

关键词：血液检测供氧激光分光法

Science-based Holistic Philosophy of Chinese Medicine Formula:Reflected in cytotoxicity of Tian-xian Liquid（in vitro） and the protein expression of p21,MMP-1 and MDR-1 in Human Colorectal Carcinoma（in vivo） in Response to Tian-xian Liquid

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Science-based Holistic Philosophy of Chinese Medicine Formul...

Geoelectrical Investigation of a Proposed Dam Site in a Sedimentary Terrain: Case Study of Aba River at Amapu-Ideobia, Akanu Ngwa Southeastern Nigeria

第十四届全国中药和天然药物学术研讨会

作者： Annballaw bridget Leigh Yau Ming Lai Tzi Bun.Ng Yao Tong Stephen Cho Wing Sze The University of Hong Kong The Hong Kong Polytechnic University The Chinese University of Hong Kong

＜正＞Aim This study aims at investigating the holistic effects of three functional constituent fractions obtained from Tian-xian Liquid（TXL）contributing to anti-tumorigenicity of TXL in human colorectal carcinoma i...

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International Journal of Geosciences 2013年第10期4卷 1376-1381页

作者： Sabinus Ikechukwu Ibeneme Kalu Kalu Ibe Alexander Olusegun Selemo Johnbosco Okechukwu Nwagbara Young Ezenwa Obioha Kingsley Obi Echendu bridget Odochi Ubechu Department of Geosciences Federal University of Technology Owerri Nigeria Department of Physics Federal University of Technology Owerri Nigeria

The geoelectrical investigation of the proposed Aba River dam at Amapu-Ideobia, Akanu Ngwa Southeastern Nigeria has been carried out. The objective of this study is to determine the downward and lateral trends of the rock layers or units along and near the proposed dam axis and deduce the possible structures that may enhance workable design of the dam. ABEM Terrameter SAS 4000 model was used and the symmetrical Schlumberger configuration was adopted. Twelve (12) Vertical Electrical Sounding stations were located and fully occupied along the dam axis. Preliminary input data from the field were fed into Zohdy software to generate real resistivities and depths to geoelectric layers. Five geoelectric layers were interpreted as Loamy Top soil, Alluvial matter, Pebble bed, Sandy lateritic and Gravely sand. Layer 1 (the top loamy soil) was encountered in VES 1, 2, 3, 4, 5, 9, 10, 11 and 12 locations with maximum thickness of 1.5 m in VES 3 and 4. Resistivity values ranged from 216 to 519 Ohm-m. The second layer (lateritic matter) had a maximum lower depth of 5 m in VES 3 and 4 points. This was not encountered in VES 6 point being replaced by alluvium. Resistivity values ranged from 101 to 6190 Ohm-m. Layer 3 was interpreted as a restricted pebble bed which occurred only at VES 6, 7 and 8 locations flanking the river course with thickness of about 3.5 m and resistivity values range of 182 415 Ohm-m. The fourth layer was modeled as the alluvial matter and restricted to the river course (VES 6, 7, 8) locations with base at between 12.5 m in VES 8 and 8 m in VES 6. The last modeled layer (Layer 5) was composed of gravely sandstone that underlined the whole study area apart from the restricted pebble bed at the NE crestal portion (VES 12). No structures like fractures, lineaments and faults that would be of deleterious effect were observed in all the VES points down to about 40 m. However, it was observed that the axial length had overriding sandy matter with high porosity and

关键词： Aba River Amapu-Ideobia Dam Axis Electrical Resistivity Geoelectric

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金属材料海洋环境生物污损腐蚀研究

科技视界 2021年第18期 139-140页

作者：刘疏影美国罗兰德帕克女校美国马里兰巴尔的摩21213

在海洋环境金属材料的腐蚀行为产生因素当中,海生物因素所带来的影响十分明显。文章针对金属材料海洋环境生物污损腐蚀进行分析,介绍了海水当中对腐蚀产生影响的海生物种类,探讨了微生物膜的结构和功能,并针对海洋环境的微生物腐蚀机理... 详细信息

在海洋环境金属材料的腐蚀行为产生因素当中,海生物因素所带来的影响十分明显。文章针对金属材料海洋环境生物污损腐蚀进行分析,介绍了海水当中对腐蚀产生影响的海生物种类,探讨了微生物膜的结构和功能,并针对海洋环境的微生物腐蚀机理进行具体阐述,希望能够为相关工作人员提供一些参考和借鉴。

关键词：金属材料海洋环境生物污损腐蚀

Profiling the Socio-Demographic Characteristics and Outcome of Preterm Delivery in Alex Ekwueme Federal University Teaching Hospital Abakaliki

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Open Journal of Obstetrics and Gynecology 2019年第8期9卷 1168-1177页

作者： Malachy Chizoba Onyema Vitus Okwuchukwu Obi Johnbosco Ifunanya Nwafor Chinwe Wendy Oliobi bridget Nkiruka Uche-Nwidagu Assumpta Nnenna Nweke Paschal Chijioke Okoye Department of Obstetrics and Gynaecology Alex Ekwueme Federal University Teaching Hospital Abakaliki Nigeria

Background: Preterm delivery is a major cause of perinatal morbidity and mortality globally. In more than half of the cases, the exact cause is unknown and it is largely unpredictable. Certain maternal, social and demographic characteristics are risk factors and often help to predict and prognosticate the neonatal outcomes. Objective: This study was designed to determine the maternal socio-demographic characteristics and neonatal outcomes of patients managed for singleton preterm delivery in Alex Ekwueme Federal University Teaching Hospital, Abakaliki. Method: This was a 4-year retrospective analysis of patients managed for preterm birth from 1st January 2012 through 31st December 2015. Results: Over the study period there were a total number of 623 singleton preterm deliveries in the facility, while there were 9647 deliveries in the facility;the preterm birth rate was 6.5% or 65 per 1000 deliveries. The mean maternal age was 28.79 ± 5.33 while the mean parity was 1.89 ± 1.98. The mean gestational age and birth weight were 33.67 ± 2.62 and 2.30 ± 0.78 kg respectively. Apgar score in 1 minute was 6.89 ± 3.27, while in the 5th minute was 7.95 ± 3.42. Majority of the patients were multiparous and booked for antenatal care in the facility. Most of the preterm labour started spontaneously and were delivered vaginally. The caesarean section rate in this study was 35.5%. Fetal distress and preeclampsia/eclampsia were the commonest indications for caesarean section. The male to female ratio was 1.1:1. Nearly half of the neonates were born with normal birth weight and 427 (68.5%) were alive at discharge. However, 196 (31.5%) suffered early neonatal death due to prematurity. Maternal parity, booking status and fetal weight were significant determinants of fetal outcome with a p-value 0.05. Conclusion: Birth weight was the most important determinant of neonatal survival and the unbooked patient was an important determinant of poor outcome. Booking for antenatal care and ensuri

关键词： Preterm Delivery Maternal Sociodemographic Characteristics Neonate

Epidemiology and Management of Ectopic Pregnancy in Alex Ekwueme Federal University Teaching Hospital, Abakaliki, Southeast, Nigeria

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Open Journal of Obstetrics and Gynecology 2019年第8期9卷 1202-1211页

作者： bridget Nkiruka Uche-Nwidagu Vitus Okwuchukwu Obi Johnbosco Ifunanya Nwafor Assumpta Nnenna Nweke Chinwe Wendy Oliobi Malachy Chizoba Onyema Paschal Chijioke Okoye Department of Obstetrics and Gynaecology Alex Ekwueme Federal University Teaching Hospital Abakaliki Nigeria

Background: Ectopic pregnancy is a common cause of maternal morbidity and mortality in the 1st trimester of pregnancy;without timely diagnosis and intervention, ruptured ectopic pregnancy can become a life threatening condition. Objective: This study aims to give baseline indices on the incidence, clinical presentation, risk factors and the management of cases of ectopic pregnancy that presented in Alex Ekwueme Federal University Teaching Hospital, Abakaliki over a 5-year period. Materials and Method: This is a 5-year retrospective study of patients who were diagnosed with ectopic pregnancy between January 1st 2012 and December 31st 2016. The statistical analysis was done using SPSS version 22. Result: During the study period, there were 11,932 deliveries while 7725 Gynaecology patients were admitted. Over the same period there were 156 patients diagnosed and managed for ectopic pregnancy, accounting for 1.31% of all deliveries and 2.0% of all Gynaecological admissions. The modal age group was 26 - 30 years 68 (43.6%), 122 (78.2%) were married, while 34 (21.7%) were single. Nulliparous were 41 (26.3%) and primiparous were 33 (21.2%). The commonest presenting complaints were lower abdominal pain and amenorrhea, and the commonest identified risk factor was previous pelvic inflammatory disease. Most of the cases were ruptured prior to presentation and partial salpingectomy was the management in all tubal pregnancy while two cases were unruptured and had salpingostomy and another case was abdominal pregnancy and had exploratory laparotomy only. Out of 156 women that presented with ectopic pregnancy, 8 (5.1%) died before surgery could be done due to late presentation. Fifty-seven women presented in a state of shock and 9 (5.8%) of the cases were complicated with acute renal failure. Conclusion: Ruptured ectopic pregnancy is a major cause of maternal morbidity and early pregnancy loss. Late presentation is a common feature in our environment;hence widespread advocacy on c

关键词： Epidemiology Management Ectopic Pregnancy Abakaliki

Active Prevention Experiencing nucleic acid test in Beijing

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ChinAfrica 2020年第8期12卷 58-58页

作者： bridget Mutambirwa 不详

A few weeks after the resurgence of COVID-19 cases in the city of Beijing,a colleague asked if I wanted to join the rest of my workmates in getting a nucleic acid *** first instinct was,NO!I don’t need a nucleic acid test,but everyone else I asked was just so calm and cool about it,making me feel kind of *** I didn’t worry about the resur-gence much at that time.

关键词： everyone nucleic Beijing