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A Com.arison of Four m.thods of Estim.ting the Scale Param.ter for the Exponential Distribution

Journal of Applied m.them.tics and Physics 2023年第10期11卷 2838-2847页

作者： Huda m. Alom.ri Departm.nt of m.them.tics Al-Baha University Al Baha KSA

In this paper, the estim.tors of the scale param.ter of the exponential distribution obtained by applying four m.thods, using com.lete data, are critically exam.ned and com.ared. These m.thods are the m.xim.m.Likelihood Estim.tor (m.E), the Square-Error Loss Function (BSE), the Entropy Loss Function (BEN) and the Com.osite LINEX Loss Function (BCL). The perform.nce of these four m.thods was com.ared based on three criteria: the m.an Square Error (m.E), the Akaike Inform.tion Criterion (AIC), and the Bayesian Inform.tion Criterion (BIC). Using m.nte Carlo sim.lation based on relevant sam.les, the com.arisons in this study suggest that the Bayesian m.thod is better than the m.xim.m.likelihood estim.tor with respect to the estim.tion of the param.ter that offers the sm.llest values of m.E, AIC, and BIC. Confidence intervals were then assessed to test the perform.nce of the m.thods by com.aring the 95% CI and average lengths (AL) for all estim.tion m.thods, showing that the Bayesian m.thods still offer the best perform.nce in term. of generating the sm.llest als.

关键词： Bayes Estim.tor m.xim.m.Likelihood Estim.tor m.an Squared Error (m.E) Akaike Inform.tion Criterion (AIC) Bayesian Inform.tion Criterion (BIC)

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紫云英与稻草混合物的矿化动态及对土壤养分和温室气体排放的影响

紫云英与稻草混合物的矿化动态及对土壤养分和温室气体排放的影响

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作者：马杰如（yahya m.ham.ed Ali Al-jerib）华中农业大学

学位级别：硕士

植物残体中营养物质的释放对农业系统的可持续性至关重要,可为微生物和植物提供碳和营养物质。植物残体的持续矿化是土壤中植物有效养分的主要来源。向土壤中添加植物残体也会影响碳循环及其储存,从而增加温室气体(CO和CH)的排放,加剧... 详细信息

植物残体中营养物质的释放对农业系统的可持续性至关重要,可为微生物和植物提供碳和营养物质。植物残体的持续矿化是土壤中植物有效养分的主要来源。向土壤中添加植物残体也会影响碳循环及其储存,从而增加温室气体(CO和CH)的排放,加剧全球变暖。植物残体的类型、其养分的初始含量、混合比、掺入时间、土壤水的可用性和温度,调控养分的释放和植物残体的矿化。土壤的化学和物理特性也可能影响植物残体养分的释放和矿化模式以及土壤中温室气体的排放。为了解养分如何从植物残体中释放,其在土壤中矿化的动态,对碳循环的影响以及土壤中温室气体的排放,在两种不同的土壤(红壤性水稻土和潮土)中进行持续180天的三个腐解实验。选取两种植物残体:1)紫云英(Astragalus sinicus L.),2)稻草(Oryza sativa L.)。植物残体的混合比例为紫云英:稻草100%:0;75%:25%;50%:50%;25%:75%和0:100%,对应的试验处理为m.m.,m.,m.以及S。第一个实验是在温室中使用埋袋法进行,以确定植物残体的分解和养分释放的速率。从淹水土壤(红壤水稻土)中选取七个采样时间(1,5,15,30,60,120和180天)。结果表明,大部分植物残体分解发生在培养的早期阶段,培养第一个月残留物各处理m.,m.,m.,m.,和S的累积分解率分别为68.7,64.1,58.6,50.3和42.4%。分解速率和养分释放速率取决于植物残体中养分的初始含量。此外,较高的养分释放速率同样发生在腐解的早期阶段。来自紫云英m.理的碳,氮和磷的累积释放率最高,然后是混合处理m.,m.,m.,最后是单一稻草处理S。进行第二个实验是为了确定残体类型、混合比和土壤性质对矿化速率和土壤肥力的影响。将植物残体按2%的比例加入到淹水土壤中,取样5次(1,15,30,60和180天),然后测定养分的浓度。结果显示在所有处理中总碳和总氮的含量随时间降低。氮的矿化取决于残留物中氮的初始含量,随残留物中氮的增加而增加。磷的矿化受土壤性质的影响,红壤水稻土中P的浓度随时间增加,在潮土中减少或保持不变。在两种类型的土壤中,稻草释放的钾最多,而紫云英处理释放的钾最少。土壤表层淹水中的养分浓度(TC,NH,NO,P,K)除钾外所有浓度均较低。第三个实验的目的是确定植物残体分解对土壤中甲烷和二氧化碳排放的影响。将2g植物残体加入到100g淹水土壤中,取样9次(1,3,5,10,15,30,60和180天)。结果显示,与对照土壤相比,由于添加了植物残留物,CH和CO排放显著增加。残留物的类型和土壤的初始特征也影响排放模式和累积排放率。在红壤稻田土中,累积的二氧化碳排放率最高为Rm.而在潮土中,最高的CO排放率来自FS处理,培养末期的排放量分别为5781.7和6551.7 m. CO-C kg土壤。两种土壤中CH的最高累积排放率均来自稻草处理(RS和FS),处理Rm.和Fm.的累积排放量较少。总体而言,作物残体的混合促进了稻草的分解和养分的释放,残体和土壤初始特性对养分矿化模式产生影响,50:50的残体混合比减少了甲烷从土壤中的排放。

关键词：紫云英稻草植物残体分解养分释放矿化甲烷二氧化碳

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新加坡最大回用水处理厂污水短程硝化厌氧氨氧化脱氮工艺

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北京工业大学学报 2015年第10期41卷 1441-1454页

作者： Cao Yeshi Kwok Bee Hong Yan Zhou Yu Liu He Jianzhong Chua Seng Chye Wah Yuen Long yahya Ghani Water Reclam.tion(Plants) Departm.nt PUB Advanced Environm.ntal Biotechnology Centre(AEBC) Nanyang Environment & Water Research InstituteNanyang Technological University Civil and Environm.nt Division National University of Singapore

总结了新加坡樟宜回用水处理厂4次采样的结果,该厂日处理城市污水80万t.在好氧区很好地实现了部分硝化和亚硝酸盐积累,其中好氧氨氧化率平均为72.2%,亚硝酸盐积累率平均为76.0%.在缺氧区氨氮和亚硝酸盐得到了同步去除(厌氧氨氧化).物料... 详细信息

总结了新加坡樟宜回用水处理厂4次采样的结果,该厂日处理城市污水80万t.在好氧区很好地实现了部分硝化和亚硝酸盐积累,其中好氧氨氧化率平均为72.2%,亚硝酸盐积累率平均为76.0%.在缺氧区氨氮和亚硝酸盐得到了同步去除(厌氧氨氧化).物料衡算结果表明:初沉池的出水总氮的37.5%是通过自养脱氮去除,27.1%是通过传统的硝化/反硝化脱氮去除,其余部分总氮则存在于活性污泥和出水中.微生物和动力学研究表明:短悬浮或游离的厌氧氨氧化菌可存在于污泥龄较短的污水处理系统.最后从出水氮质量浓度、pH、碱度、曝气能耗及反应器容积等方面,将樟宜回用水处理厂的分段进水活性污泥法工艺与新加坡其他3个回用水处理厂的m.L/LE工艺进行了对比分析.

关键词：污水自养脱氮处理厌氧氨氧化亚硝酸盐积累自养脱氮城市污水处理温带气候

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Im.act of Irrigation on Food Security in Bangladesh for the Past Three Decades

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Journal of Water Resource and Protection 2009年第3期1卷 216-225页

作者： m. Wakilur RAHm.N Lovely PARVIN 不详

Bangladesh has m.de im.ressive progress in agriculture sector in the last three decades and has alm.st be-com. self-sufficient in food grain production. This is a trem.ndous achievem.nt owing to its sm.ll territory and huge population and this was achieved through agricultural m.chanization and m.dernization. Irrigation is one of the leading inputs has direct influence to increase yield, food grains production and plays vital role for ensuring food security in Bangladesh. The present study exam.ned the growth of irrigated area and its im.act on food grain production during last three decades. Tim. series data were used for the study. Differ-ent statistical m.thods such as m.an, percentage, linear and exponential growth m.del were applied for get-ting m.aningful findings. Various technologies have been used for irrigating crops which have contributed to rapid expansion of irrigated area. The conventional irrigation m.thods (Low Lift Pum., Dhone, Swing Bas-ket, Treadle Pum. etc.) were replaced by m.dern m.thods (i.e Deep Tube Well and Shallow Tube Well). In addition, surface water irrigation also sharply declined, losing its im.ortance due to lack of new surface irri-gation project and the ineffectiveness of earlier project. Groundwater covered 77 percent of total irrigated area and m.jor (62%) extractions occurred through Shallow Tube Wells (STWs). The rapid expansion of ground water irrigation in respect to STWs irrigation was due to governm.nt’s withdrawal on restrictions on tube well setting rule, encouraging private sector and the cost effectiveness of Chinese engine which have been affordable to the sm.ll and m.dium.farm.rs. Irrigated area thus, increased by about three tim.s and cropping intensity also increased from.154 to 176 percent. Boro rice, an irrigated crop, consum.d 73 percent of the total crop irrigation and contributed to a greater extent in total rice production in Bangladesh. Boro rice alone contributed to 55 percent of total food grain and was als

关键词： Irrigation Food Security Boro Rice and food Grain Production

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Am.hetam.ne Versus Non Am.hetam.ne-Related First Episode Psychosis in Saudi Arabian Patients

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Pharm.cology & Pharm.cy（药理与制药） 2011年第3期

作者： Ehab Said EL Desoky Ashraf m.A El-Tantawy Yasser m. Raya Abdulham.ed Al-yahya

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A Conservative Pressure-Correction m.thod on Collocated Grid for Low m.ch Num.er Flows

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World Journal of m.chanics（力学国际期刊） 2012年第5期

作者： S. m. yahya S. F. Anwer S. Sanghi

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Potential Regulators of Sporadic als Developm.nt and Alternative Therapeutic Options

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Neuroscience & m.dicine 2015年第1期6卷 5-12页

作者： m.renci m. m.nning m.rie Kelly-Worden Ball State University Muncie USA

Am.otrophic Lateral Sclerosis (als) is the m.st com.on neurodegenerative disorder. It is also am.ng the m.st lethal as life expectancy is between 2 and 5 years after diagnosis. Sporadic als (sals) m.kes up 90% of all als cases with little known about the exact m.chanism.of pathogenesis. m.ny potential regulators of sals developm.nt have been proposed, several of which are exam.ned in this review with supporting evidence. Interplay am.ng these factors is exam.ned m.re closely in hopes of shedding m.re light on sals pathophysiology. There is a paucity of effective treatm.nt options as the only FDA-approved drug for use, riluzole, has a positive but m.dest benefit in im.roving survival. Other treatm.nts available m.rely target am.liorating sym.tom. of als. Alternative treatm.nt options are also discussed. This study ultim.tely aim. to m.ke relevant connections am.ng factors im.licated in sals developm.nt and to highlight alternative form. of treatm.nt in im.roving neuron function and status, albeit controversial.

关键词： Am.otrophic Lateral Sclerosis als Sporadic als Neurodegeneration

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Am.liorating the re/dehydrogenation behaviour of m.H2 by zinc titanate addition

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镁合金学报(英文) 2023年第6期11卷 2205-2215页

作者： N.A.Ali N.A.Sazelee m.F.m. Din m.m.Nasef A.A.Jalil Haizen Liu m.Ism.il Energy Storage Research Group Faculty of Ocean Engineering Technology and InformaticsUniversiti Malaysia Terengganu21030 Kuala NerusTerengganuMalaysia Departm.nt of Electrical and Electronic Engineering Faculty of EngineeringNational Defence University of MalaysiaKem Sungai BesiKuala LumpurMalaysia Center of Hydrogen Energy Institute of Future EnergyUniversiti Teknologi Malaysia81310 UTM Johor BahruJohorMalaysia Departm.nt of Chem.cal and Environm.ntal Engineering Malaysia Japan International Institute of TechnologyUniversiti Teknologi MalaysiaJalan Sultan Yahya PetraKuala Lumpur 54100Malaysia Faculty of Chem.cal and Energy Engineering Universiti Teknologi Malaysia81310 UTM Johor BahruJohorMalaysia Guangxi Novel Battery m.terials Research Center of Engineering Technology State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite StructuresSchool of Physical Science and TechnologyGuangxi UniversityNanning 530004China State Key Laboratory of Featured m.tal m.terials and Life-cycle Safety for Com.osite Structures Nanning 530004China

m.gnesium.hydride(m.H_(2))is the m.st feasible and effective solid-state hydrogen storage m.terial,which has excellent reversibility but initiates decom.osing at high tem.eratures and has slow kinetics ***,zinc titanate(Zn_(2)TiO_(4))synthesised by the solid-state m.thod was used as an additive to lower the initial tem.erature for dehydrogenation and enhance the re/dehydrogenation behaviour of m.H_(2).With the presence of Zn_(2)TiO_(4),the starting tem.erature for the dehydrogenation of m.H_(2)was rem.rkably lowered to around 290℃–305℃.In addition,within 300 s,the m.H_(2)–Zn_(2)TiO_(4)sam.le absorbed 5.0 wt.%of H_(2)and 2.2–3.6 wt.%H_(2)was liberated from.the com.osite sam.le in 30 m.n,which is faster by 22–36 tim.s than as-m.lled m.H_(2).The activation energy of the m.H_(2)for the dehydrogenation process was also downshifted to 105.5 k J/m.l with the addition of Zn_(2)TiO_(4)indicating a decrease of 22%than as-m.lled m.H_(2).The superior behaviour of m.H_(2)was due to the form.tion of m. Zn_(2),m.O and m.TiO_(3),which are responsible for am.liorating the re/dehydrogenation behaviour of m.H_(2).These findings provide a new understanding of the hydrogen storage behaviour of the catalysed-m.H_(2)system.

关键词： Hydrogen storage Solid-state storage m.H_(2) Additive Zn_(2)TiO_(4)

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Electronic packaging m.terials prepared by powder injecting m.lding and pressure infiltration process

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Rare m.tals 2007年第6期26卷 625-629页

作者： YIN Fazhang GUO Hong JIA Chengchang XU Jun ZHANG Xim.n ZHU Xuexin National Engineering and Technology Research Center for Nonferrous m.tals Com.osites Beijing General Research Institute for Nonferrous Metals Beijing 100088 China m.terials Science and Engineering School University of Science and Technology Beijing Beijing 100083 China

alsiCp （65 vol.% SiC） electronic packaging m.terials were m.nufactured by powder injection m.lding （PIm. and pressure infiltration process in order to obtain near net-shaped parts. SiCp preform.d com.acts obtained by pre-sintering process at 1150 K have high strength and good appearance, and the ratio of open porosity to total porosity is nearly 98%. The relative density of com.osites is bigger than 99%. The therm.l conductivity of A1SiCp com.osites fabricated by this m.thod is 198 W·m.-1·K^-1, and the coefficient of therm.l expansion （CTE） is 8.0 × 10^-6/K （298 K）.

关键词： com.osites alum.num m.crostructure therm.l conductivity

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Actual Practical Attitude and Knowledge of Dental Im.lants am.ng Senior Dental Students and General Dentists Graduated from.Som. Saudi and Non-Saudi Dental Schools

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International Journal of Clinical m.dicine（临床医学国际期刊） 2023年第1期

作者： m.ham.ed m. A. Abdullah Al-Abdaly Sam. yahya Alam.i Ghadeer m.ham.ed m.ham.ed Al-Abdaly Ayed Abdulrahm.n Abdullah

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