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单宁酸对苹果黑霉病防治的研究

单宁酸对苹果黑霉病防治的研究

作者： KPADONOU ESSEDOLO narcisse（纳希斯）辽宁大学

学位级别：硕士

苹果是中国培育最广的水果之一,营养丰富,味道甘甜且富含抗氧化剂,深受人们喜爱。但苹果的货架期却因苹果果实采后腐烂病的发生而缩短,且造成了巨大经济损失。寻求一种高效、安全的防治手段,用于水果采后腐烂病的防治,正成为一种新的趋... 详细信息

苹果是中国培育最广的水果之一,营养丰富,味道甘甜且富含抗氧化剂,深受人们喜爱。但苹果的货架期却因苹果果实采后腐烂病的发生而缩短,且造成了巨大经济损失。寻求一种高效、安全的防治手段,用于水果采后腐烂病的防治,正成为一种新的趋势。单宁酸是从植物中提取一种多元酚类物质,以单宁酸为研究对象,链格孢菌为病原菌。一方面,探究单宁酸对该病原菌的抑菌机理;另一方面,探究单宁酸对苹果腐烂病的防治效果、理化性质及其能否诱导机体产生抗病性,抵御病原菌的入侵。为单宁酸能否用于苹果采后腐烂病的防治提供理论依据,以期开发一种环境友好的新型生物防腐剂。主要研究结果如下:1.探究单宁酸对链格孢菌的抑菌机理。一方面,单宁酸显著抑制链格孢菌的生长速率,破坏菌丝原本形态,对链格孢菌的生长起抑制作用,并确定5.0mg/m L为最适单宁酸抑菌浓度,具有较好的抑菌效果;另一方面,单宁酸处理通过抑制己糖激酶(HK)、果糖-6-磷酸激酶(PFK)、丙酮酸激酶(PK)活性,使其反应物葡萄糖含量升高,终产物丙酮酸含量降低,进而影响糖酵解途径的正常运行。2.探究单宁酸对苹果腐烂病的防治效果、理化性质及其能否诱导机体产生抗病性。单宁酸对苹果黑斑病的防治效果结果表明,经单宁酸处理的苹果,其防治效果为60%左右,并确定5.0 mg/m L为最适单宁酸防治浓度,具有较好的防治效果。单宁酸对苹果本身理化性质影响结果表明,经单宁酸处理的苹果,其硬度品质提高,糖度并无显著影响,一定程度上改善了苹果本身的品质。诱导抗性实验结果表明,单宁酸处理会提高苹果总酚、类黄酮含量及苯丙氨酸解氨酶(PAL)活性,促进机体苯丙烷代谢途径的运行;经单宁酸处理后,苹果果实的几丁质酶、β-1,3-葡聚糖酶等病程相关蛋白的含量显著提高了。以上结果表明,单宁酸处理能够诱导苹果产生抗病性,延缓苹果采后因病原菌侵染而引起的腐烂变质,对苹果黑斑病起到防治效果。综上,单宁酸处理不仅抑制了链格孢菌的生长,而且提高了苹果果实抵抗链格孢菌入侵的能力,一定程度上改善了果实品质。该研究结果为苹果采后黑斑病防治提供了新的思路和方向。

关键词：单宁酸链格孢菌抑菌机理诱导抗性

毛里塔尼亚海域日本鲭时空分布与海洋环境的关系

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上海海洋大学学报 2020年第6期29卷 868-877页

作者：宋利明许回陈明锐 EBANGO NGANDO narcisse 上海海洋大学海洋科学学院上海201306 国家远洋渔业工程技术研究中心上海201306 大洋渔业资源可持续开发教育部重点实验室上海201306 远洋渔业协同创新中心上海201306

根据2017年9月20日至12月31日在毛里塔尼亚海域112个站点的调查数据,研究日本鲭(Scomber japonicus)的时空分布规律,并采用分位数回归的方法对随机选取的78%的站点数据建立其单位捕捞努力量渔获量(catch per unit effort,CPUE)与叶绿素... 详细信息

根据2017年9月20日至12月31日在毛里塔尼亚海域112个站点的调查数据,研究日本鲭(Scomber japonicus)的时空分布规律,并采用分位数回归的方法对随机选取的78%的站点数据建立其单位捕捞努力量渔获量(catch per unit effort,CPUE)与叶绿素a浓度、海表面温度、海表面盐度的关系模型,并利用剩余22%的站点数据验证所建立的模型的有效性,利用广义加性模型(GAM)评价环境因子的影响程度。根据分位数模型,计算日本鲭的栖息地综合指数(integrated habitat index,IHI),对建模站点和验证站点的CPUE实测值与预测值进行Wilcoxon(符号秩)检验,用Spearman相关系数结合双尾检验,检验其CPUE实测值与预测值之间的相关性,分析IHI与CPUE的关系。结果表明:海表面温度对日本鲭CPUE的影响最显著,其次是温盐的交互作用和海表面盐度,叶绿素a浓度对其无显著影响;建模站点和验证站点的CPUE预测值与实测值间皆无显著性差异;IHI模型对CPUE具有良好的预测效果;IHI分布较高的海域为17°25′W~17°45′W和20°15′N~20°45′N。根据上述结果,建议我国渔船在下半年作业时,作业范围应集中在17°25′W~17°45′W和20°15′N~20°45′N区域,以提高渔获产量。

关键词：日本鲭时空分布海洋环境分位数回归栖息地综合指数毛里塔尼亚水域

Effects of Crassocephalum bauchiense (Hutch) leaf aqueous extract on toxicity indicators and reproductive characteristics in Oryctolagus cuniculus exposed to potassium dichromate

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Asian pacific Journal of Reproduction 2019年第6期8卷 276-282页

作者： Ferdinand Ngoula Margaret Mary Momo Chongsi Omer Bébé Kenfack Ngouateu Alexane Marquise Ndekeng Makona Augustave Kenfack Bertin narcisse Vemo Joseph Tchoumboue Department of Animal Science Faculty of Agronomy and Agricultural SciencesUniversity of DschangCameroon Department of Animal Biology and Physiology Faculty of SciencesUniversity of Yaounde ICameroon

Objective:To evaluate the effects of Crassocephalum(C.)bauchiense(Hutch)leaf aqueous extract on the biochemical markers of toxicity,oxidative stress indicators and reproductive parameters in rabbit does(Oryctolagus cuniculus)exposed to potassium ***:A total of 36 nulliparous and sexually mature female rabbit does,aged 8 months and weighing 2.8-3.0 kg,were divided into 6 groups of 6 *** mating,group T0 received distilled water(1 mL/kg body weight),while groups T0-,VC100,AE100,AE200 and AE400 were treated with 40 mg/mL/kg body weight of potassium *** addition,group VC100 received 100 mg/mL/kg body weight of vitamin C,while groups AE100,AE200 and AE400 received aqueous extract of *** leaves at 100,200 and 400 mg/mL/kg body weight,by oral gavage for 27 days,*** the 28th daypost-co?tum,animals were *** indicators such as creatinine,urea,alanine amino tranferase,aspartate amino transferase,total protein and total cholesterol were measured by using a *** stimulating hormone,luteinizing hormone and progesterone were measured by enzyme-linked immuno sorbent *** stress markers like malondialdehyde,catalase,superoxide dismutase and total peroxidase in ovary homogenates were measured by ***:Serum concentrations of urea,creatinine,alanine aminotransferase,aspartate aminotransferase and total cholesterol were significantly higher(P<0.05),and total protein level was significantly lower in T0-group(receiving potassium dichromate only)compared to other *** of ethanolic extract of *** significantly decreased serum concentrations of urea,creatinine,alanine aminotransferase,aspartate aminotransferase and total cholesterol,and significantly increased total protein ***,ethanolic extract of *** no significant effect on the foetotoxic *** serum concentrations of follicle stimulating hormone and l

关键词： Crassocephalum bauchiense Foetotoxicity Potassium dichromate Rabbit doe Reproduction

Microstructure of Fine Clay Soils Stabilized with Sugarcane Molasses

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Open Journal of Civil Engineering 2022年第2期12卷 247-269页

作者： narcisse Malanda Nice Ngouallat Mfoutou Erman Eloge Nzaba Madila Paul Louzolo-Kimbembe National Upper Polytechnic School Marien Ngouabi University Brazzaville Republic of Congo Department of Chemistry Biochemistry and Physics and Hydrogen Research Institute University of Quebec in Trois-Rivières Trois-Rivières Canada National Upper Education School Marien Ngouabi University Brazzaville Republic of Congo

Sugar cane molasses has proved cohesive and excellent performance on soil aggregates (fine particles). However, the microstructure of consolidated soil by the molasses is not yet subjected to research. The analysis results of sample without molasses (0%) and consolidated samples at 8%, 12%, and 16% show that the molasses acts on the structure of clayey fine soil developing its microstructure of airy matrix type (sample without molasses (0%) to a microstructure of a qualified type, more solid. Consolidated samples to 8%, 12%, 16% of molasses). We also observe the presence of inter-aggregate pores (mesopores) of similar size in all samples. The results of porosimetrical analyses (BJH) of the sample without molasses and consolidated samples to 8%, 12%, and 16% show that simultaneous porous volumes of samples are reduced with the increasing of molasses quantity. This latter, therefore, acts on the porous volume (micropore 2 nm and mesopore 9 nm) by reducing them which really means, molasses occupies the porous volume of the sample. However, this sample seems not to have any effect on the size of mesopores 9 nm. Thus, this product induces the evolution of the soil structure towards the highly dense and condensed structure. Consequently, materials in consolidated soil by molasses will have mechanical properties far superior to those of materials consolidated soil without molasses.

关键词： Microstructure Consolidated Clayey Fine Soil Molasses of Sugar Cane Mesopore Micropore Specific Surface Area

Effect of Wood Waste on Acoustic and Magnetic Properties of Composite Bricks and Correlation between Sound Velocity and Magnetic Induction in These Bricks

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Open Journal of Composite Materials 2020年第1期10卷 15-25页

作者： Gilbert Ganga Adolphe Kimbonguila Manounou narcisse Malanda Michel Dzondo Gadet Timothée Nsongo National Advanced School of Engineering University Marien Ngouabi Brazzaville Congo Center for Research and Initiation of Technology Projects (CRIPT) Brazzaville Congo Laboratory of Mechanics Energtics and Engineering ENSP-UMNG Brazzaville Congo Facultyof Sciences and Technology University Marien Ngouabi Brazzaville Congo Center of Géological and Mining Research Brazzaville Congo

In the present study, kambala (botanical name: Chlorophora excelsa and Chlorophora regia) wood wastes were incorporated into stabilized earth bricks in order to test their acoustic insulation capacity of the walls;leading to better waste management from the timber industry. Two methods have been applied to determine the influence of the wood waste content in the stabilized earth bricks, on the weakening of the level of noise reception coming from the environmental medium, in an apartment built with composite bricks (earth + wood chips + cement). This influence has also been analyzed on the magnetic field induced by these bricks. The results showed that the level of sound reception through these bricks decreases with increasing wood waste content regardless of the method used (from 110 dB to 68 dB, respectively for Φb = 0% and Φb = 8%). The kambala wood waste in cement-stabilized clay bricks induces a magnetic field that increases with the wood waste content;the high contents of the wood chips causing an increase in the magnetic permeability of the composite medium. The correlation between the noise level and the magnetic field of the bricks shows that the noise level declines with increasing magnetic induction of the bricks.

关键词： Kambala Tree Wood Waste Clay Brick Sound Velocity Magnetic Field

Impact of pH Water and Mineralogical Microstructure of Soil Mixed with Wood Waste on the Compressive Strength of Composite Bricks;and Bricks Resistance Modeling

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Open Journal of Civil Engineering 2020年第1期10卷 9-21页

作者： Gilbert Ganga narcisse Malanda Diogène Pongui Ngoma Timothée Nsongo Michel Dzondo Gadet National Advanced School of Engineering University Marien NGouabi Brazzaville Congo Center for Research and Initiation of Technology Projects (CRIPT) Brazzaville Congo Laboratory of Mechanics Energtics and Engineering ENSP-UMNG Brazzaville Congo Faculty of Science and Technology University Marien NGouabi Brazzaville Congo Centerof Géological and Mining Research (CRGM) Brazzaville Congo

This study includes the manufacture of cement stabilized clay bricks with embedded mahogany chips. The impact of this waste and its interaction with water in the bricks was evaluated on the mechanical properties. The compressive strength tests using a universal press were carried out on bricks with and without adding wood chips. The results obtained show that the incorporation of wood chips into the bricks decreases the compressive strength. This reduction in compressive strength led us to conduct an analysis of clay and water as intrinsic factors, before and after incorporation of untreated wood waste. Thus, a mineralogical analysis of the clay with and without mahogany chips was made using an X-ray diffractometer, using an anticathode of cobalt with the line Κα, of wavelength λ = 1789Å. After quantification of the mineral constituents, it is noted that the concentration of SiO2 decreases considerably in the clay with addition of wood chips, resulting in the reduction of the compressive strength in these composite materials (from Rc = 9.26 MPa at 0% of chips to 3.55 MPa at 8%). A mathematical model following the interpolations of Lagrange was then proposed. The analysis of the water resulting from the impregnation of dry wood chips in the water, shows that the water becomes strongly acid (pH = 4.3 at the 7th day of immersion), thus contributing to the reduction of resistance. This analysis of intrinsic factors will allow future studies to take into account the treatment of wood waste by different processes in order to increase the mechanical, thermal and acoustic properties of composite bricks with the same contents, thus generating massive support for the use of its composite materials.

关键词： Clay Bricks Mineralogical Analysis Wood Chips Compressive Strength pH Water

Concrete Formulation Study for Informal and Semi-Informal Construction Sectors

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Open Journal of Civil Engineering 2019年第1期9卷 57-79页

作者： narcisse Malanda Paul Louzolo-Kimbembe Louis Ahouet Jarlon Brunel Makela Guy-Richard Mouengue National Polytechnic High School Marien Ngouabi University Brazzaville Congo Normal High School Marien Ngouabi University Brazzaville Congo Building and Public Works Control Office Brazzaville Congo

The present work consisted in carrying out a study on the effective formulation of concrete for an optimal resistance to compression (fc28) between 20 and 30 MPa for the sites animated by the actors of the informal and semi-informal sectors of the construction. Studies have been carried out on projects under construction, by taking samples of fresh concrete in order to evaluate their real compressive strengths. These surveys show that there is a problem in the concrete formulation, as nearly 2/3 of the results show the lack of technical knowledge on concrete formulation practices. Indeed, on eight sites surveyed and whose fresh concrete samples were taken, only two sites (7 and 8) report fairly consistent results. Their 28-day compressive strength values are respectively 35.36 and 22.18 MPa. In addition, various formulations proposed with aggregates from different quarries or extracts from the bed of the Congo River, were determined in the laboratory. This study allowed us to obtain fairly objective results overall, which is characteristic of concretes of required quality. Of the six (06) formulation proposals, average resistances of 19.6 MPa at 07 days and 25.28 MPa at 28 days were obtained. These results at 28 days are in the range of 20 to 30 MPa, set as objective in this study. These formulations can be a reliable source for concrete manufacturers in these construction sectors. Similarly, the statistical study based on principal component factor analysis tests has shown that the most appropriate formulation, in terms of mechanical resistance, is that proposed with sand extracted from the Congo River (formulation 3). This is justified by the fact that this sand is consistent and has a good granular distribution.

关键词： Formulation Concretes Aggregates Cement Physico-Mechanical Characteristics Informal and Semi-Formal Sectors

Thermo-Mechanical Properties Study of Stabilized Soil Bricks to Sugar Cane Molasses and Cassava Starch Binders

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Open Journal of Applied Sciences 2023年第2期13卷 240-260页

作者： narcisse Malanda Jean Albin Nkaya Gilbert Ganga Ngambara Emamou Nondel Durvy Paul Louzolo-Kimbémbé Polytechnic National Superior School (ENSP) Marien Ngouabi University Brazzaville Republic of the Congo Superior Normal School (ENS) Marien Ngouabi University Brazzaville Republic of the Congo National Institute for Research in Engineering Sciences Innovation and Technology (INRSIIT) Brazzaville Republic of the Congo

The current study deals Swith thermo-mechanical properties of stabilized soil small bricks with the help of organic binders of sugar cane molasses and cassava starch. Different formulations of soil concrete have been suggested after the geotechnical characterization of samples of soil was taken. From these, it arises that the studied soil is the most plastically clay (of type A3) according to GTR classification. Samples made of small bricks and measured out at 4%, 6% and 8% of binders (molasses, starch or molasses + starch) have been warmed up to different temperatures (100°C, 150°C, 200°C and 250°C) for the rising of the thermic behavior under different conditions and submitted to crushing testings for the estimation of characteristic resistances to the compression. According to the mechanical behavior, we note an improvement of resistances for small bricks measured 4%, 6% and 8%, of molasses respectively of 32.44%, 32.06% and 23.43% against the value of reference for small bricks without molasses. In the same way, the binder (molasses + starch) also reveals an improvement of resistance to the compression of 13.27%, 26.17% and 26.17%. On the contrary, the stabilization with the starch binder did not bring a significative improvement. According to the thermic influence, the heating at 100°C of stabilized small bricks at 4%, 6% and 8% of molasses, reveals a significative improvement of resistances. Moreover, the stabilization with the starch reveals on the contrary a good behavior for heatings at 150°C and 250°C. In short, for the binder (molasses + starch), it is the heating at 200°C that shows some improvements of remarkable resistances. Different analyses of realized statistics also show the effectivity of obtained results. For all realized formulations, the measuring out at 6% of binders (molasses, or molasses + starch) seems as optimal in front of the best thermo-mechanical revealed properties.

关键词： Clay Molasses Cassava Starch Heating Compressed Soil Brick Mechanical Resistance

Retro Placental Hematoma: Maternal and Fetal Prognosis at the Maternity of the University Hospital of Bouake

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