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爆破 2024年第2期41卷 15-22,169页

作者：张光辉张家托王洋程远龙蒋宏杰陈明湖北能源集团罗田平坦原抽水蓄能有限公司黄冈438000 武汉大学水利水电学院武汉430072

硬质岩隧洞的轮廓成型效果对提高围岩稳定性和降低支护成本具有重要意义。以优化隧洞轮廓孔单孔装药量和装药结构为目标,首先,理论分析了隧洞爆破中轮廓孔装药参数的取值范围;其次,分别以1200 g、900 g、750 g、600 g的单孔装药量进行... 详细信息

硬质岩隧洞的轮廓成型效果对提高围岩稳定性和降低支护成本具有重要意义。以优化隧洞轮廓孔单孔装药量和装药结构为目标,首先,理论分析了隧洞爆破中轮廓孔装药参数的取值范围;其次,分别以1200 g、900 g、750 g、600 g的单孔装药量进行了硬质岩隧洞爆破试验,并借助激光扫描仪对隧洞轮廓成型效果进行了扫描分析;最后,利用断裂力学模型分析了不同单孔装药量的隧洞轮廓成型效果。结果表明:当硬质岩隧洞的轮廓孔装药参数在合理范围内时,单孔装药量越小,爆破产生的孔间裂缝数量越少,岩体损伤范围也越小;当装药量由1200 g降低至600 g时,隧洞轮廓超挖体积由6.53 m^(3)降低至2.02 m^(3),但由孔位误差导致的轮廓欠挖体积由0.15 m^(3)增大0.26 m^(3);断裂力学模型在硬质岩隧洞轮廓爆破的模拟中优于损伤模型,模型计算得隧洞轮廓上的半孔数与观察值吻合较好。研究成果可为类似硬质岩隧洞爆破开挖中轮廓成型效果优化提供技术与方法借鉴。

关键词：隧洞爆破轮廓爆破单孔装药量空气间隔装药断裂力学模型

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Development of micro milling force model and cutting parameter optimization

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中国有色金属学会会刊：英文版 2012年第S3期22卷 851-858页

作者： Shih-ming WANG Da-fun CHEN Min-chang jang Shambaljamts TSOOJ Department of Mechanical Engineering Chung Yuan Christian University

Taking the minimum chip thickness effect,cutter deflection,and spindle run-out into account,a micro milling force model and a method to determine the optimal micro milling parameters were *** micro milling force model was derived as a function of the cutting coefficients and the instantaneous projected cutting area that was determined based on the machining parameters and the rotation trajectory of the cutter *** an allowable micro cutter deflection is defined,the maximum allowable cutting force can be *** optimal machining parameters can then be computed based on the cutting force model for better machining efficiency and *** verify the proposed cutting force model and the method to determine the optimal cutting parameters,micro-milling experiments were conducted,and the results show the feasibility and effectiveness of the model and method.

关键词： micro-milling cutting force spindle run out cutter deflection optimal parameter

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环保纤维型钻机刹车块制备及性能评价

化学工程师 2024年第2期38卷 83-86,91页

作者：邱崇粤林世明江毅唐琳中海油能源发展股份有限公司工程技术湛江分公司广东湛江524057 中海油常州涂料化工研究院有限公司上海海铠防腐工程技术分公司广东深圳518052 中海油服油田化学事业部湛江作业公司广东湛江524057 中海油服钻井事业部湛江作业公司广东湛江524057

传统石棉型钻机刹车块在高温工作条件下易脱落,且产生有毒致癌分解物。本文以环保纤维型材料制备的盘式钻机刹车块作为实验,各项性能实验结果,表明纤维型钻机刹车块的密度、冲击强度、摩擦系数、磨损率性能与石棉型钻机刹车块基本相似,... 详细信息

传统石棉型钻机刹车块在高温工作条件下易脱落,且产生有毒致癌分解物。本文以环保纤维型材料制备的盘式钻机刹车块作为实验,各项性能实验结果,表明纤维型钻机刹车块的密度、冲击强度、摩擦系数、磨损率性能与石棉型钻机刹车块基本相似,符合行业标准要求,且制动导热温度比石棉型钻机刹车块低,因此,纤维型钻机刹车块性能稳定,使用寿命较长,利于作业人员健康及设备工作效率。

关键词：钻机刹车块冲击强度摩擦性能玻璃纤维石棉

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专用肥用量对油菜籽产量及品质的影响

中国油料作物学报 2024年第2期46卷 359-369页

作者：方雯任涛刘方舟蒋博鲁明星张哲鲁剑巍华中农业大学资源与环境学院/农业农村部长江中下游耕地保育重点实验室/华中农业大学微量元素研究中心湖北武汉430070 湖北省油菜办公室湖北武汉430070 全国农业技术推广服务中心北京100125

肥料是保障农作物生长的重要物质基础,油菜专用配方肥施用作为油菜轻简化种植的关键技术在生产中广泛应用,明确兼顾丰产和优质双重目标的油菜专用配方肥适宜用量将为油菜绿色高质生产提供关键技术支撑。通过2020-2021年在湖北省江陵县... 详细信息

肥料是保障农作物生长的重要物质基础,油菜专用配方肥施用作为油菜轻简化种植的关键技术在生产中广泛应用,明确兼顾丰产和优质双重目标的油菜专用配方肥适宜用量将为油菜绿色高质生产提供关键技术支撑。通过2020-2021年在湖北省江陵县、沙洋县及洪湖市等3个地点的田间试验,设置了0、450、600、750和900 kg/hm^(2)5个肥料用量,研究不同专用配方肥用量对油菜产量、产量构成因子、养分含量及品质的影响。施用专用配方肥可显著提高单株角果数、每角粒数及千粒重,进而提升油菜籽产量。与不施肥处理相比,专用配方肥施用量为900kg/hm^(2)时,单株角果数、每角粒数及千粒重平均值分别增加277.4%、17.9%和9.2%,油菜籽增产率达300%。油菜专用配方肥的施用显著影响了油菜籽油分及蛋白质含量,与不施肥处理相比,油菜籽蛋白质含量在专用配方肥用量为900 kg/hm^(2)时最高,增长率为16.0%~34.6%,而含油量最低,相较于不施肥降低了4.4%~11.6%。相关性分析表明,增施专用肥显著增加了油菜籽产量、含水率、蛋白质、芥酸及脂肪酸组成,减少了油菜籽硫甙含量。兼顾产量、油菜籽品质和饲用等方面,专用肥用量控制在750~900 kg/hm^(2)时,能够在获得较高的菜籽产量及蛋白质产量的同时,菜籽中硫甙、芥酸及饱和脂肪酸的生成增幅较小并提高了产油量。要在油菜增产的基础上继续追求品质提升,可结合不同地力条件,适量增加中微量元素,以进一步提高油菜籽含油率和改善脂肪酸的组成,实现产量与品质的协同。

关键词：油菜专用肥适宜用量产量品质相关性分析

S-(-)-尼古丁-己二酸盐的制备、特性及其应用研究

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化学研究与应用 2024年第9期36卷 2184-2189页

作者：肖智心李江黄晓江何世波刘明星湖北工业大学生命科学与健康工程学院湖北武汉430068 湖北和诺生物工程股份有限公司湖北恩施445000

S-(-)-尼古丁的获取主要是通过从烟叶等植物中提取,获取途径受限,本研究以2′-羟基尼古丁为原料通过还原、化学拆分制备S-(-)-尼古丁;选用己二酸与S-(-)-尼古丁通过超声法制备S-(-)-尼古丁-己二酸盐,优化了合成工艺。产物利用ESI-MS、^(... 详细信息

S-(-)-尼古丁的获取主要是通过从烟叶等植物中提取,获取途径受限,本研究以2′-羟基尼古丁为原料通过还原、化学拆分制备S-(-)-尼古丁;选用己二酸与S-(-)-尼古丁通过超声法制备S-(-)-尼古丁-己二酸盐,优化了合成工艺。产物利用ESI-MS、^(1)H NMR、HPLC进行表征;采用HPLC进行抗氧化性分析;利用热重分析仪进行热稳定性分析。结果表明在反应的最佳工艺条件下S-(-)-尼古丁总产率达55.1%,比旋光度为-141.5°,光学纯度为99.23%;S-(-)-尼古丁-己二酸盐的产率达94.4%,纯度为99.36%;S-(-)-尼古丁-己二酸盐的抗氧化性和热稳定性均优于S-(-)-尼古丁。本研究提供了一条切实可行的S-(-)-尼古丁及其己二酸盐的合成路线;S-(-)-尼古丁-己二酸盐有效避免了S-(-)-尼古丁易氧化、受热不稳定等不足,具有良好的应用前景。

关键词： S-(-)-尼古丁 S-(-)-尼古丁-己二酸盐抗氧化性热稳定性

Intense blue-emitting Ca_2PO_4Cl:Eu^(2+) phosphor for near-ultraviolet converting white light-emitting diodes

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Journal of Rare Earths 2010年第S1期28卷 250-253页

作者： Yi-Chen Chiu Chun-Kuei Chang Yao-Tsung Yeh Shyue-ming jang Material and Chemical Research Laboratories Industrial Technology Research Institute Phosphors Research Laboratory and Department of Applied Chemistry National Chiao Tung University

A blue phosphor Ca2PO4Cl:Eu2+(CAP:Eu2+) was synthesized by solid state *** Ca2PO4Cl:Eu2+ exhibited high quantum efficiency and excellent thermal *** luminescent intensity of Ca2PO4Cl:Eu2+ was found to be 128% under excitation at 380 nm,149% under 400 nm,and 247% under 420 nm as high as that of BaMgAl10O17:Eu2+.The optimal doping concentration was observed to 11 mol.% of CAP:Eu2+.The energy transfer between Eu2+ ions in CAP were occurred via electric multipolar interaction,and the critical transfer distance was estimated to be 1.26 nm.A mixture of blue-emitting Ca2PO4Cl:Eu2+,green-emitting(Ba,Sr)2SiO4:Eu2+ and red-emitting CaAlSiN3:Eu2+ phosphors were selected in conjunction with 400 nm chip to fabricate white LED *** average color-rendering index Ra and correlated color temperature(Tc) of the white LEDs were found to be 93.4 and 4590 K,*** results indicated that it was a promising candidate as a blue-emitting phosphor for the near-UV white light-emitting diodes.

关键词： Ca2PO4Cl:Eu2+ phosphors luminscense rare earths

Cooperative hunting in a discrete predator-prey system

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International Journal of Biomathematics 2020年第7期13卷 133-158页

作者： Yunshyong Chow Sophia R-J.jang Hua-ming Wang Institute of Mathematics Academia Sinica Taipei 10617Taiwan Department of Mathematics and Statistics Texas Tech University LubbockTX 79409USA Department of Statistics Anhui Normal University Wuhu 241003AnhuiP.R.China

We propose and investigate a discrete-time predator-prey system with cooperative hunting in the predator *** model is constructed from the classical Nicholson-Bailey host-parasitoid system with density dependent growth rate.A sufficient condition based on the model parameters for which both populations can coexist is derived,namely that the predator’s maximal reproductive number exceeds *** study existence of interior steady states and their stability in certain parameter *** is shown that the system behaves asymptotically similar to the model with no cooperative hunting if the degree of cooperation is *** cooperative hunting,however,may promote persistence of the predator for which the predator would otherwise go extinct if there were no cooperation.

关键词： Cooperative hunting discrete predator-prey system predator persistence Neimark-Sacker bifurcation

Impact of COVID-19 on liver

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World Journal of Clinical Cases 2021年第27期9卷 7998-8007页

作者： Yu-jang Su Chen-Wang Chang ming-Jen Chen Yen-Chun Lai Department of Emergency Medicine MacKay Memorial HospitalTaipei City 10449Taiwan Poison Center Department of Emergency MedicineMacKay Memorial HospitalTaipei City 10449Taiwan Yuanpei University of Medical Technology HsinChu 30015Taiwan MacKay Junior College of Medicine Nursing and ManagementTaipei City 25245Taiwan Department of Medicine MacKay Medical CollegeNew Taipei City 25245Taiwan Division of Gastroenterology and Hepatology Department of Internal MedicineMacKay Memorial HospitalTaipei City 10449Taiwan Department of Anesthesiology Taipei Medical University HospitalTaipei City 110301Taiwan Heroic Faith Medical Science Company Taipei 11493Taiwan

The incidence of liver injury after coronavirus disease 2019(COVID-19)infection ranged from 15%-53%.The mechanism includes direct viral cytopathic effect,cytokinesis,and treatment drug-induced liver *** symptoms include nausea,vomiting,diarrhea,and loss of *** laboratory results include increased liver enzyme levels,decreased monocyte count,and longer prothrombin *** most common imaging findings are hepatomegaly on ultrasound,ground-glass opacity on chest computed tomography(CT),and liver hypodensity and pericholecystic fat stranding on abdominal *** may also have different presentations and poor outcomes of different liver diseases concomitant with COVID-19 *** function test(LFT)results should be monitored,and all factors known to cause or predispose liver injury should be investigated while managing the *** risks of transfer to an intensive care unit,need for mechanical ventilator support,and acute kidney injury is higher in COVID-19 patients with than without abnormal *** mortality and length of hospital stay are both observed.

关键词： COVID-19 Fatty liver Liver cirrhosis Hepatitis Hypoalbuminemia Hepatic injury

Cecal lipoma with subclinical appendicitis: A case report

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World Journal of Clinical Cases 2019年第2期7卷 209-214页

作者： Kuen-jang Tsai Yun-Sheng Tai Chao-ming Hung Yue-Chiu Su Department of Surgery E-Da Cancer Hospital I-Shou University Department of Surgery E-Da Hospital I-Shou University Department of Pathology E-Da Cancer Hospital I-Shou University

BACKGROUND Colonic lipomas are rare, slow-growing benign tumors. Colonic lipomas are generally asymptomatic and are found incidentally. Although cases of cecal lipoma have been sporadically reported in the literature, the disease has not been systematically *** SUMMARY We present a 44-year-old man who underwent a routine physical check-up during which colonoscopic examination revealed an asymptomatic 1.5-cm cecal mass at the appendiceal orifice. Laparoscopic exploration was performed that also demonstrated a congested and erythematous appendix. En bloc resection of both the cecum and vermiform appendix was performed because of the suspicion of malignancy. Histopathological examination revealed a cecal lipoma composed of mature adipose tissue, and the appendix showed subclinical *** procedures and findings were discussed, along with relevant English literature that was retrieved from the PubMed database from 2000 to ***-six cases, including ours, were reported. Consistent with the findings of the literature, it is difficult to obtain a definitive diagnosis by colonoscopic *** Surgery remains the treatment of choice for this condition. Intraoperative frozen pathological sectioning helped the surgeon decide the extent of surgery, and radical surgery was avoided. Excision of benign lesions occupying the appendiceal orifice may be indicated for the prevention of later development of acute appendicitis. The prognosis is generally good, with only one of the 26 reported patients complicated with acute appendicitis, who subsequently succumbed due to severe comorbidities and sepsis.

关键词： Cecal lipoma Appendicitis Intussusception Case report