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输电线电磁场和人的健康

世界科学 1986年第9期 39-41页

作者： m.granger morgan ,H.Keeth Florig ,Indira Nair ,David Lincoln ,李荣庆

人门受功频电磁场辐射对健康能否产生严重的不良后果? 首先在美国海军协助下,后来又在美国纽约州的电能研究学会能量研究部和其他单位协助下,一项高质量的、有意义的研究项目已经完成。科研人员仍然不能断定功频(60赫兹)电磁场能否对人... 详细信息

人门受功频电磁场辐射对健康能否产生严重的不良后果? 首先在美国海军协助下,后来又在美国纽约州的电能研究学会能量研究部和其他单位协助下,一项高质量的、有意义的研究项目已经完成。科研人员仍然不能断定功频(60赫兹)电磁场能否对人的健康有严重的影响。短暂地受到甚至较强的电磁场辐射显然对

关键词：电磁场电磁学辐射能电场辐射输电线仔猪电热毯追溯性电力局原子键共价键极低频瑞典北欧剂量用药量说服力动物

Enhancing the Resilience of Electricity Systems

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Engineering 2017年第5期3卷 580-582页

作者： Ben A. Wender m. granger morgan K. John Holmes Board on Energy and Environmental Systems Division on Engineering and Physical Sciences The National Academies of Sciences Engineering and Medicine Washington DC20001 USA Department of Engineering and Public Policy Carnegie Mellon University Pittsburgh PA 15213 USA

1.引言经过超级飓风桑迪和飓风哈维、厄玛、何塞、玛利亚、卡特里娜等重大干扰事件的影响,以及2003年美国东北部的大停电事件,美国对具备恢复力的电力系统的需求越加凸显,也更加意识到电力基础设施对恶意物理和网络攻击的脆弱性。尽管... 详细信息

1.引言经过超级飓风桑迪和飓风哈维、厄玛、何塞、玛利亚、卡特里娜等重大干扰事件的影响,以及2003年美国东北部的大停电事件,美国对具备恢复力的电力系统的需求越加凸显,也更加意识到电力基础设施对恶意物理和网络攻击的脆弱性。尽管事后新闻媒体立即对事件进行了大量的报道。

关键词：恢复力 resilience 电力系统停电事件电力基础设施网络攻击 electricity 干扰事件卡特里娜美国东北部

Low-temperature processing of screen-printed piezoelectric KNbO3 with integration onto biodegradable paper substrates

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microsystems & Nanoengineering 2023年第1期9卷 271-282页

作者： morgan m.monroe LGuillermo Villanueva Danick Briand École Polytechnique Fédérale de Lausanne(EPFL) Soft Transducers LaboratoryInstitute of Mechanical Engineering2000NeuchâtelSwitzerland École Polytechnique Fédérale de Lausanne(EPFL) Advanced NEMS LaboratoryInstitute of Mechanical Engineering1015LausanneSwitzerland

The development of fully solution-processed,biodegradable piezoelectrics is a critical step in the development of green electronics towards the worldwide reduction of harmful electronic ***,recent printing processes for piezoelectrics are hindered by the high sintering temperatures required for conventional perovskite fabrication ***,a process was developed to manufacture lead-free printed piezoelectric devices at low temperatures to enable integration with eco-friendly substrates and electrodes.A printable ink was developed for screen printing potassium niobate(KNbO3)piezoelectric layers in microns of thickness at a maximum processing temperature of 120℃ with high *** parallel plate capacitor and cantilever devices were designed and manufactured to assess the quality of this ink and evaluate its physical,dielectric,and piezoelectric characteristics;including a comparison of behaviour between conventional silicon and biodegradable paper *** printed layers were 10.7–11.2μm thick,with acceptable surface roughness values in the range of 0.4-1.1μ*** relative permittivity of the piezoelectric layer was *** poling parameters were optimised for the piezoelectric response,with an average longitudinal piezoelectric coefficient for samples printed on paper substrates measured as d33,eff,paper=13.57±2.84 pC/N;the largest measured value was 18.37 pC/N on paper *** approach to printable biodegradable piezoelectrics opens the way forward for fully solution-processed green piezoelectric devices.

关键词： KNbO3 piezoelectric integration

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为什么需要地球工程学?

科技创业 2010年第4期 12-13页

作者： m·格兰杰·摩根（m.granger morgan）卡内基梅隆大学工程和公共政策系

m·格兰杰·摩根解释了为什么我们必须研究为地球遮光所产生的后果。科学家们已经知道了如何使地球快速降温。秘密就在于地球工程学：具体来说，就是在平流层中使用微粒子反射太阳光。用这种方法为地球遮光的直接成本与减少二氧化碳排... 详细信息

m·格兰杰·摩根解释了为什么我们必须研究为地球遮光所产生的后果。科学家们已经知道了如何使地球快速降温。秘密就在于地球工程学：具体来说，就是在平流层中使用微粒子反射太阳光。用这种方法为地球遮光的直接成本与减少二氧化碳排放成本相比，连百分之几都不到。既然反射太阳光既快捷又便宜，为什么还要与所有现今存在的问题——集体行动以实现减排中所面临的——进行斗争昵？为什么不等到我们遇到气候问题时．再如此简单地解决它呢？

关键词：地球工程学二氧化碳排放直接成本快速降温气候问题太阳光科学家微粒子

Design concerns of room and pillar retreat panels

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International Journal of mining Science and Technology 2017年第1期27卷 29-35页

作者： Klemetti Ted m. Sears morgan m. Tulu Ihsan B. mining Engineer Ground Control Branch NIOSH Office of Mine Safety and Health ResearchPittsburghPAUSA

Why do some room and pillar retreat panels encounter abnormal conditions？ What factors deserve the most consideration during the planning and execution phases of mining and what can be done to mitigate those abnormal conditions when they are encountered7 To help answer these questions, and to determine some of the relevant factors influencing the conditions of room and pillar （R ＆ P） retreat min- ing entries, four consecutive R ＆ P retreat panels were evaluated. This evaluation was intended to rein- force the influence of topographic changes, depth of cover, multiple-seam interactions, geological conditions, and mining geometry. This paper details observations were made in four consecutive R ＆ P retreat panels and the data were collected from an instrumentation site during retreat mining. The pri- mary focus was on the differences observed among the four panels and within the panels themselves. The instrumentation study was initially planned to evaluate the interactions between primary and secondary support, but produced rather interesting results relating to the loading encountered under the current mining conditions. In addition to the obse^ation and ｜ll^trumentation, numerical modeling was per- formed to evaluate the stress condi~!ons. Both the Lamodel 3.0 and Rocscience Phase 2 programs were used to evaluate these four panels, The results of both models indicated a drastic reduction in the vertical stresses experienced in these panels due to the full extraction mining in overlying seams when compared to the full overburden load. Both models showed a higher level of stress associated with the outside entries of the panels. These results agree quite well with the observations and instrumentation studies performed at the mine. These efforts provided two overarching conclusions concerning R ＆ P retreat mine planning and execution. The first was that there are four areas that should not be overlooked during R ＆ P retreat mining： topographic relief, multiple^seaPa str

关键词： Room and pillar Retreat mining Deep coverSafety multiple seam

Initial impacts of rain gardens＇ application on water quality and quantity in combined sewer： field-scale experiment

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Frontiers of Environmental Science & Engineering 2017年第4期11卷 127-138页

作者： Isam Alyaseri Jianpeng Zhou Susan m. morgan Andrew Bartlett Department of Civil Engineering Al-Muthanna University Alsamawah Al-Muthanna 72001 Iraq Department of Civil Engineering Southern Illinois University Edwardsville Edwardsville IL 62026 USA Graduate School Southern Illinois University Edwardsville Edwardsville IL 62026 USA Agricultural Statistics Laboratory University of Arkansas Fayetteville AR 72701 USA

Green infrastructures such as rain gardens can benetit onsite reduction ot stormwater runott, leading to reduced combined sewer overflows. A pilot project was conducted to evaluate the impact of rain gardens on the water quality and volume reduction of storm runoff from urban streets in a combined sewer area. The study took place in a six-block area on South Grand Boulevard in St. Louis, missouri. The impact was assessed through a comparison between the pre-construction （2011/2012） and the post-construction （2014） phases. Shortly after the rain gardens were installed, the levels of total suspended solids, chloride, total nitrogen, total phosphorous, zinc, and copper increased. The level of mercury was lower than the detection level in both phases. E. coli was the only parameter that showed statistically significant decrease following the installation of rain gardens. The likely reason for initial increase in monitored water quality parameters is that the post-construction sampling began after the rain gardens were constructed but before planting, resulted from soil erosion and wash-out from the mulch. However, the levels of most of water quality parameters decreased in the following time period during the post-construction phase. The study found 76% volume reduction of stormwater runoff following the installation of rain gardens at one of studied sites. Statistical analysis is essential on collected data because of the encountered high variability of measured flows resulted from low flow conditions in studied sewers.

关键词： Rain gardens Bioretention Combined sewer Stormwater quality and quantity

Preliminary rib support requirements for solid coal ribs using a coal pillar rib rating(CPRR)

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International Journal of mining Science and Technology 2021年第1期31卷 15-22页

作者： Khaled mohamed mark Van Dyke Gamal Rashed morgan mSears Robert Kimutis National Institute for Occupational Safety and Health Pittsburgh Mining Research DivisionPittsburghPA 15236USA

Researchers from the National Institute for Occupational Safety and Health(NIOSH)are developing a coal pillar rib rating(CPRR)technique to measure the integrity of coal *** CPRR characterizes the rib composition and evaluates its impact on the inherent stability of the coal *** CPRR utilizes four parameters:rib homogeneity,bedding condition,face cleat orientation with respect to entry direction,and rib *** these parameters are measurable in the field.A rib data collecting procedure and a simple sheet to calculate the CPRR were *** developed CPRR can be used as a rib quality mapping tool in underground coal mines and to determine the potential of local rib instabilities and support requirements associated with overburden *** calculations were conducted for 22 surveyed solid coal ribs,mainly composed of coal *** on this study,the rib performance was classified into four categories.A preliminary minimum primary rib support density(PRSD)line was obtained from these surveyed *** sample cases are presented that illustrate the data collection form and CPRR calculations.

关键词： Coal rib stability Rib support design Coal pillar rib rating Rib quality mapping CPRR Coal classification

Coal rib response during bench mining: A case study

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International Journal of mining Science and Technology 2018年第1期28卷 107-113页

作者： morgan m.Sears John Rusnak mark Van Dyke Gamal Rashed Khaled mohamed michael Sloan Ground Control Branch NIOSH Pittsburgh Mining Research Division

In 2016, room-and-pillar mining provided nearly 40% of underground coal production in the United *** the past decade, rib falls have resulted in 12 fatalities, representing 28% of the ground fall fatalities in *** coal *** of these 12 fatalities(75%) have occurred in room-andpillar *** objective of this research is to study the geomechanics of bench room-and-pillar mining and the associated response of high pillar ribs at overburden depths greater than 300 *** paper provides a definition of the bench technique, the pillar response due to loading, observational data for a case history, a calibrated numerical model of the observed rib response, and application of this calibrated model to a second site.

关键词： Deep cover Bench mining Thick seam Retreat mining Rib response Rib support

Choledochal cysts: Similarities and differences between Asian and Western countries

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World Journal of Gastroenterology 2019年第26期25卷 3334-3343页

作者： George N Baison morgan m Bonds William S Helton Richard A Kozarek Digestive Disease Institute Virginia Mason Medical Center

Choledochal cysts(CCs)are rare bile duct dilatations,intra-and/or extrahepatic,and have higher prevalence in the Asian population compared to Western *** of the current literature on CC disease originates from Asia where these entities are most *** are thought to arise from an anomalous pancreaticobiliary junction,which are congenital anomalies between pancreatic and bile *** similarities in presentation between Eastern and Western patients exist such as female predominance,however,contemporary studies suggest that Asian patients may be more symptomatic on *** though CC disease presents with an increased malignant risk reported to be more than 10%after the second decade of life in Asian patients,this risk may be overstated in Western *** this difference in cancer risk,management guidelines for all patients with CC are based predominantly on observations reported from Asia where it is recommended that all CCs should be excised out of concern for the presence or development of biliary tract cancer.

关键词： Choledochal cyst Cholangiocarcinoma Asian populations Western populations Anomalous pancreaticobiliary junction