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Chinese Physics B 2012年第7期21卷 551-558页

作者： Jijoy.P.mathew George Varghese jacob mathew Thin Film Research Laboratory Department of PhysicsSt.Berchmans CollegeChanganasseryKerala 686101India Department of Physics Calicut UniversityThenjippalamKeralaIndia

ZnO thin films were synthesised by a new method which uses polyvinyl alcohol （PVA） as the polymer precursor. The films are annealed at different temperatures and for different annealing times. The structural parameters, like grain size, lattice constants, optical band gap, and Urbach energy, depend on the annealing temperature and time. All the films possess tensile strain, which relaxes as the annealing temperature and time increase. The photoluminescence （PL） spectra contain only ultraviolet （UV） peaks at low temperature, but as the annealing temperature and time increase, we observe peaks at the blue and green regions with a variation in the intensities of these peaks with annealing temperature and time.

关键词： stress, band gap, Urbach energy photoluminescence

如何利用直流/直流转换器提高射频功率放大器的效率

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电子技术应用 2007年第1期33卷 I0001-I0007页

作者： mathew jacob 美国国家半导体应用技术工程师

CDMA/WCDMA移动电话一向采用的射频功率放大器都直接由电池为其提供电这个设计的好处是系统更易配置，但缺点是CDMA/WCDMA标准对线性功率放大器有特殊的要求，令这种放大器无论输出高还是低的发射功率，都受其内在结构所限而无法充分发... 详细信息

CDMA/WCDMA移动电话一向采用的射频功率放大器都直接由电池为其提供电这个设计的好处是系统更易配置，但缺点是CDMA/WCDMA标准对线性功率放大器有特殊的要求，令这种放大器无论输出高还是低的发射功率，都受其内在结构所限而无法充分发挥其效率。

关键词：射频功率放大器直流/直流转换器 WCDMA标准线性功率放大器移动电话发射功率

Watch your step!Common reef injuries in Hawaii and treatment options

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Journal of Coastal Life Medicine 2015年第2期 166-168页

作者： jacob mathew Jr. Department of Medicine Tripler Army Medical CenterHonoluluHawaiiUSA

As more people flock to coastal areas such as Hawaii for vacation,many may find themselves coming into contact with coral reef for the first *** it’s through snorkeling,swimming,scuba diving,or surfing,the reef can pose a serious danger to anyone not familiar with this delicate life *** it may appear to be a rock,it is actually a living creature that is home to multiple strains of *** bacteria can quickly invade injuries sustained from contacting reef,leading to tissue infections ultimately require surgical *** this review,we provide a background on coral reef and its common associated *** there are no evidenced based treatments currently available,anecdotal interventions can be considered.

关键词： Coral reef Urchin Hawaii Abrasions Injury

A New Accident Prediction Model for Highway-Rail Grade Crossings Using the USDOT Formula Variables

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Journal of Traffic and Transportation Engineering 2020年第1期8卷 1-13页

作者： jacob mathew Rahim F Benekohal Civil and Environmental Engineering University of Illinois Urbana-ChampaignNewmark Civil Engineering Building205 N.Mathews AveUrbana 61801IllinoisUSA

This paper presents the ZINDOT model,a methodology utilizing a zero-inflated negative binomial model with the variables used in the United States Department of Transportation(USDOT)accident prediction formula,to determine the expected accident count at a highway-rail grade *** model developed contains separate formulas to estimate the crash prediction value depending on the warning device type installed at the crossing:crossings with gates,crossings with flashing lights and no gates,and crossings with *** proposed methodology also accounts for the observed accident count at a crossing using the Empirical Bayes *** ZINDOT model estimates were compared to the USDOT model estimates to rank the crossings based on the expected accident *** is observed that the new model can identify crossings with a greater number of accidents with Gates and Flashing Lights and Crossbucks in both Illinois(data which were used to develop the model)and Texas(data which were used to validate the model).A practitioner already using the USDOT formulae to estimate expected accident count at a crossing could easily use the ZINDOT model as it employs the same variables used in the USDOT *** methodology could be used to rank highway-rail grade crossings for resource allocation and safety improvement.

关键词： Highway-rail grade crossing accident prediction USDOT formulae zero inflated negative binomial empirical Bayes

γ-氨基丁酸转氨酶灭活剂——3-氨基4-氟丁酸的高效合成法

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氨基酸和生物资源 1986年第3期14卷 31-33页

作者： jacob mathew 祝洪山

一种在体内有效的γ-氨基丁酸转氨酶灭活剂——3-氨基4-氟丁酸(1)的合成是分两步进行的。把叔丁基醋酸锂与氟乙腈缩合,生成物用氰硼酸钠在酸性甲醇中还原成1。

关键词：灭活剂高效合成叔丁基盐酸甲醇振摇硼酸钠癫痛乙酸乙醋糊状物三颈瓶

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提高电池供电应用系统的电源效率

电子设计应用 2003年第7期 70-72页

作者： mathew jacob Frank De Stasi 美国国家半导体公司

开关式电源的效率可以接近 100% ,但在低负载电流工作下其效率则会大幅下降,甚至低于线性稳压器。采用断续导电模式 (DCM) 再配合多种不同的操作模式,可以提高开关式电源的效率。

关键词：电池供电应用系统电源效率开关式电源开关稳压器负载电流

Spectroscopic studies of gel-grown lanthanum malonate crystals

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Journal of Rare Earths 2012年第3期30卷 245-249页

作者： Varghese mathew Sabu jacob Lizymol Xavier K.E.Abraham Department of Physics St.Aloysius'CollegeEdathua-689573India Department of Physics S.B.CollegeChanganacherry-686101India

Lanthanum malonate crystals were grown by single tube ionic diffusion through silica gel. The crystallinity of the grown crystals was analyzed by powder X-ray diffraction studies. Fourier transform infrared spectroscopy （FTIR） and fourier transform （FT） Raman studies confirmed the presence of functional groups in the title compound. The optical band gap energy of the material was extracted from diffuse reflectance spectrum.

关键词： lanthanum malonate crystal growth X-ray diffraction analysis DRS studies FTIR and FT Raman studies rare earths

Influence of La3+ ion in the yttria matrix in improving the microhardness of infrared transparent nano LaxY2-xO3 sintered via hybrid heating

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Journal of Advanced Ceramics 2017年第3期6卷 240-250页

作者： Jijimon K. THOMAS mathew C. T. jacob KOSHY Sam SOLOMON Electronic Materials Research Laboratory Department of Physics Mar Ivanios College Thiruvananthapuram 695015 Kerala India

In the present work, hybrid sintering technique which couples the resistive heating and microwave heating is employed to sinter infrared transparent La0.15Y1.85O3 to 99.2% of the theoretical density for the first time to the best of our knowledge. The presence of La3+ in the yttria matrix improves the hardness properties to a greater extent without affecting the transmittance properties, but there is a deterioration in the thermal properties of the sample. So we have limited our studies to La0.15Y1.85O3 which shows better optical, thermal, and hardness properties. The pellets fabricated from the ultra-fine nano powder with average particle size of ~12 nm synthesized by combustion technique and sintered at 1430 ℃ with an average grain size of 0.22 μm show ~80.1% transmittance in the UV–visible region and 81% in mid infrared region. For a comparative study of the optical, mechanical, and thermal properties, two other variants of sintering strategies namely conventional sintering and microwave sintering are also employed. A comprehensive analysis on the hardness reveals that the hardness of the pellets sintered via hybrid heating is 9.73 GPa and is superior to the pellets sintered using the other two techniques. The thermal conductivity of the sample is also analyzed in detail. The results clearly indicate that the La0.15Y1.85O3 ultra-fine nano powder synthesised by the single-step combustion method and sintered via microwave hybrid heating shows better transmittance properties without compromising the mechanical properties, and can be used very effectively for the fabrication of infrared transparent windows and domes.

关键词： La3+ concentration microhardness hybrid sintering infrared transparent ceramics thermal conductivity

Performance of Four Rice Cultivars Transplanted Monthly over Full Year under Irrigated Conditions in Tanzania

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Rice science 2015年第2期22卷 71-80页

作者： Nobuhito SEKIYA Aristarick Cyril SHAYO mathew Kaozya jacob Nobuaki OIZUMI Motonori TOMITAKA Hideki ARAKI Japan International Cooperation Agency (JICA) JICA Tanzania Office Institute for Sustainable Agroecosystem Services Graduate School of Agricultural and Life SciencesUniversity of Tokyo Kilimanjaro Agricultural Training Centre Experimental Farm Faculty of AgricultureYamaguchi University Ministry of Agriculture Training Institute Ilonga Japan International Cooperation Agency JICA Headquarters

In Tanzania, the phenology and seasonal variations of the yields of different rice cultivars have rarely been studied, especially under fully-irrigated conditions. A trial was conducted to identify the most suitable calendar for rice production in Tanzania under fully-irrigated conditions. Four popular rice cultivars, NERICA1, Wahiwahi, IR64 and TXD306, were transplanted monthly from January to December 2011. The four cultivars recorded similarly higher or lower yields than the annual means when transplanted in July （0.50-0.57 kg/m2） and April （0.07-0.31 kg/m2）. A yield-ranking analysis showed that plants transplanted in July was the most productive while those transplanted in April was the least productive, and also revealed a yield-seasonality for irrigated rice in Tanzania, a low-yield season （April-May）, a high-yield season （June-August）, and an unstable-yield season （September-March）. These yield seasons would appear to be closely linked to seasonal temperature variations. When transplanted in April-May, plants were exposed to very low temperatures between panicle initiation and flowering, apparently reducing yield through cold-induced sterility. Those transplanted in June-August prolonged their growth under relatively low temperatures and increased yield through increasing biomass production. In September- March, yield levels varied greatly due to the shortened phenological growth durations at higher temperatures. We conclude that under fully-irrigated conditions in Tanzania, rice should be transplanted in July to ensure the maximum production and yield stability. The yield-seasonality suggests that implementing measures to protect plants from low and high temperature stress at critical phenological stages may allow year-round rice production under fully-irrigated conditions in Tanzania.

关键词： irrigated rice local variety phenological response temperature yield component yieldperformance

Functional and clinical outcome with modified lateral approach total hip arthroplasty in stiff hips with ankylosing spondylitis

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World Journal of Orthopedics 2022年第8期13卷 714-724页

作者： mathew Kiran jacob Pavan Kumar Reddy Roncy Savio Kuruvilla Chandy Viruthapadavil John Pradeep mathew Poonnoose Anil Thomas Oommen Unit 2 Department of OrthopaedicsChristian Medical College HospitalVellore 632004India

BACKGROUND Ankylosing spondylitis at total hip arthroplasty(THA)has significant hip stiffness with flexion deformity,restricted mobility,and *** of movement(ROM)improvement with good functional outcome is seen following THA in these *** modified Hardinge approach without abductor compromise is helpful in these stiff hips with associated flexion *** To assess improvement in ROM and functional outcomes with a modified lateral approach THA in ankylosing spondylitis with stiff *** A total of 69 hips that underwent THA with a modified Hardinge approach in 40 patients were evaluated at a mean follow-up of 38.33 *** individuals ambulated with weight-bearing as tolerated and ROM exercises from the 1st postoperative *** Harris hip score and ROM were assessed during *** of life assessments using the 36-item and 12-item short form health surveys were done along with clinical and functional outcomes at *** 22.0 was used for statistical *** correlation of ROM and functional score change was performed using Pearson’s correlation *** Sixty-nine hips with a significant decrease in ROM preoperatively with 32 clinically fused hips showed significant improvement in flexion *** mean flexion in 69 hips improved from 29.35±31.38 degrees to 102.17±10.48 *** mean difference of 72.82 with a P value<0.0001 was *** total,45 out of 69 hips had flexion deformity,with 13 hips having a deformity above 30 *** flexion during the follow-up was below 90 degrees in 3 *** hips had flexion of 90 degrees at follow-up,while the remaining 55 hips had flexion above 100 *** Harris hip score improved from 17.03±6.02 to 90.66±7.23(P value<0.0001).The 36-item short form health survey at the follow-up indicated health status in 40 patients as excellent in 11,very good in 20,good in 5,fair in 3,and poor in *** mean mental health score was 84.10±*** relief w

关键词： Ankylosing Spondylitis Stiff flexion deformity Harris hip score Hip range of movement 36-item short form health survey score Total hip arthroplasty modified Hardinge approach