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MPS型磨煤机制粉系统动态模型与瞬态运行优化控制研究
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作者 王朝阳 石慧 +4 位作者 王文毓 许朋江 范建林 刘明 严俊杰 《中国电机工程学报》 EI CSCD 北大核心 2024年第16期6518-6528,I0019,共12页
为提升MPS型磨煤机制粉系统变出力过程关键参数的控制精度,该文建立并验证制粉系统动态模型,开展控制策略优化研究。在原逻辑基础上,提出考虑煤质水分信息的前馈磨煤机入口一次风温控制回路,以优化控制策略。开展煤质水分增加、给煤速... 为提升MPS型磨煤机制粉系统变出力过程关键参数的控制精度,该文建立并验证制粉系统动态模型,开展控制策略优化研究。在原逻辑基础上,提出考虑煤质水分信息的前馈磨煤机入口一次风温控制回路,以优化控制策略。开展煤质水分增加、给煤速率增加、磨煤机变出力等瞬态过程模拟研究,获得制粉系统关键参数瞬态特征和能耗特性,验证所提出策略的优越性。结果表明:采用优化的控制逻辑后,系统在应对煤质水分突变、煤量突变等扰动时的响应速率增加、磨煤机出口风粉温度波动范围减小50%以上、瞬态能耗下降2.4%。磨煤机在变出力过程中,稳态能耗可降低100 kW以上,制粉过程能耗降低6.82%,瞬态过程中磨煤机出口风温的波动幅度下降50%、响应时间缩短10%以上、可实现瞬态节能5.43%,保障制粉系统的运行安全并降低能耗。在燃煤发电机组中应用提出的制粉系统优化控制逻辑,可降低燃煤发电机组变负荷瞬态过程中负荷率、主汽压力等关键参数的运行偏差,提高机组的运行灵活性。 展开更多
关键词 mpS型磨煤机 制粉系统 动态模型 变出力 瞬态能耗 控制优化
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Noah-MP陆面模式对干旱区不同下垫面水热通量模拟评估
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作者 杨扬 杨启东 《沙漠与绿洲气象》 2024年第1期28-37,共10页
基于干旱区张掖国家气候观象台2021年1月-2022年6月和大满灌区绿洲农田站2020年1-12月的观测数据,评估Noah-MP模式对干旱区荒漠和农田两种下垫面的水热通量的模拟性能。结果表明:Noah-MP模式模拟的干旱区荒漠下垫面辐射与观测值的相关... 基于干旱区张掖国家气候观象台2021年1月-2022年6月和大满灌区绿洲农田站2020年1-12月的观测数据,评估Noah-MP模式对干旱区荒漠和农田两种下垫面的水热通量的模拟性能。结果表明:Noah-MP模式模拟的干旱区荒漠下垫面辐射与观测值的相关系数均>0.98,泰勒评分>0.93。感热的泰勒评分(0.809)>潜热的泰勒评分(0.504),对辐射及湍流通量的变化特征、峰谷值与观测值总体一致,模拟效果较好。模拟的5 cm土壤湿度对降水过程有明显的响应,表现出明显的冷暖季差异,但其模拟性能仍有待改进。Noah-MP模式模拟的干旱区农田下垫面辐射通量及各层土壤温度的相关系数均>0.98,泰勒评分>0.58,模拟效果较理想。但模拟的潜热通量及各层土壤湿度较观测值偏低,尤其在生长季模拟性能不理想。Noah-MP模式对干旱区荒漠下垫面水热通量的模拟性能优于农田下垫面,优化和发展模式水文过程的参数化方案,在模式中考虑人为作用,是提高干旱区陆面过程模式模拟能力的重要方向。 展开更多
关键词 干旱区 Noah-mp模式 水热通量 荒漠和农田下垫面
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贵州地区急性淋巴细胞白血病儿童TPMT、NUDT15基因多态性与6-MP耐受性分析
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作者 王彩丽 方常莹 《贵州医药》 2024年第1期27-29,共3页
目的观察贵州地区ALL儿童TPMT、NUDT15基因多态性,探讨其与6-MP耐受性的关系。方法收集贵阳市儿童医院血液科住院的贵州地区ALL儿童。Sanger法检测患者NUDT15c.415C>T和TPMT*2、TPMT*3A、TPMT*3B、TPMT*3C基因型。所有ALL儿童均按CCL... 目的观察贵州地区ALL儿童TPMT、NUDT15基因多态性,探讨其与6-MP耐受性的关系。方法收集贵阳市儿童医院血液科住院的贵州地区ALL儿童。Sanger法检测患者NUDT15c.415C>T和TPMT*2、TPMT*3A、TPMT*3B、TPMT*3C基因型。所有ALL儿童均按CCLG-2008方案化疗,每周1次监测血常规及肝肾功能。根据2016新编WHO化疗药物毒性反应分度标准,出现Ⅲ~Ⅳ度与6-MP相关的毒性反应,称为6-MP不耐受(除外感染、其他药物影响)。分析TPMT、NUDT15基因多态性与6-MP不耐受的相关性。结果共纳入患者60例,检测到TPMT突变(中间代谢型)3例(5%),正常代谢型57例(95%)。NUDT15基因CT型12例(20%),TT型1例(1.7%),CC型(野生型)47例(78.3%)。NUDT15基因突变率21.7%(13/60)显著高于TPMT基因突变率5%(3/60),差异有统计学意义(P=0.007)。TPMT突变型3例均发生6-MP不耐受(100%),NUDT15突变型13例中11例发生6-MP不耐受(84.6%)。结论TPMT、NUDT15基因突变与6-MP不耐受相关(P<0.05),联合检测TPMT、NUDT15基因对调整6-MP使用,减少6-MP不良反应提供依据。 展开更多
关键词 6-mp TPMT NUDT15 基因多态性 贵州地区 急性淋巴细胞白血病 儿童
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Methylprednisolone accelerate chest computed tomography absorption in COVID-19:A three-centered retrospective case control study from China 被引量:1
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作者 Lan Lin Dan Xue +2 位作者 Jin-Hua Chen Qiong-Ying Wei Zheng-Hui Huang 《World Journal of Clinical Cases》 SCIE 2022年第2期426-436,共11页
BACKGROUND Based on the results of some large randomized controlled trials(RCTs)confirmed the efficacy of corticosteroids in coronavirus disease 2019(COVID-19),corticosteroids have been included in World Health Organi... BACKGROUND Based on the results of some large randomized controlled trials(RCTs)confirmed the efficacy of corticosteroids in coronavirus disease 2019(COVID-19),corticosteroids have been included in World Health Organization guidelines,but remain controversial.AIM To investigate the efcacy and safety of low-to-moderate dose(30 to 40 mg/d)short-term methylprednisolone for COVID-19 patients.METHODS The clinical data of 70 patients diagnosed with COVID-19 who received antiviral therapy with Arbidol for 7-10 d before admission but had no obvious absorption on chest computed tomography(CT)imaging were retrospectively analyzed.Arbidol(as the control group)and methylprednisolone(as the corticosteroid group)were given respectively after admission.After treatment,chest CT was reexamined to evaluate the absorption of pulmonary lesions.Additionally,we evaluated and compared the lymphocyte count,erythrocyte sedimentation rate(ESR),interleukin-6(IL-6),serum ferritin,lactate dehydrogenase(LDH),creatine kinase-MB(CK-MB),hypersensitive C-reactive protein(hs-CRP)and D-dimer levels,and also analyzed the incidence of toxic and side effects.RESULTS All patients in the corticosteroid group had varying degrees of CT absorption,which was significantly better than that in the control group(CT obvious absorption rate:89.47%vs 12.5%,P<0.05).The average daily dose and course of methylprednisolone in the patients with significant improvement on chest CT was(38.55±13.17)mg and(6.44±1.86)d respectively.During the treatment,the lymphocyte count,ESR,IL-6,serum ferritin,LDH,CK-MB,hs-CRP and D-dimer levels all improved gradually,indicating that both Arbidol and methylprednisolone therapy were contributed to improving the condition of COVID-19 patients.The corticosteroid regimen did not prolong the clearance time of severe acute respiratory syndrome coronavirus 2.There were no severe adverse reactions such as gastrointestinal bleeding,secondary severe infection,hypertension,diabetic ketoacidosis,mental disorders or electrolyte disorders during the whole corticosteroid treatment process.CONCLUSION Low-to-moderate dose short-term methylprednisolone can accelerate the chest CT imaging absorption of COVID-19 so as to improve symptoms and alleviate the condition in a short term,reduce the hospital stay,meanwhile avoid severe COVID-19 phases.The protocol has been proven to be effective and safe in clinical use. 展开更多
关键词 Coronavirus disease 2019 CORTICOSTEROID methylprednisolone Treatment
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High-dose methylprednisolone can induce remissions in patients with fludarabine- refractory chronic lymphocytic leukaemia 被引量:5
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作者 Xu, W Miao, KR Hong, M Zhu, DX Fang, C Dong, HJ Wang, DM Cao, X Li, JY 《南京医科大学学报(自然科学版)》 CAS CSCD 北大核心 2010年第11期1550-1550,共1页
关键词 临床医学 诊断 HDmp CLL
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铜基漆酶模拟酶Cu-MP的制备及活性研究 被引量:1
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作者 孙艺格 徐晨 +3 位作者 曹红 高云玲 李成 郑兰兰 《中国有色金属学报》 EI CAS CSCD 北大核心 2024年第1期314-328,共15页
天然漆酶的催化活性和稳定性易受外界环境因素的不良影响,受天然漆酶活性中心和电子转移的启发,利用6-巯基嘌呤与铜离子的配位反应合成一种新型漆酶模拟酶(Cu-MP),并采用SEM-EDS、BET、FTIR、XRD、XPS对其性能进行表征并分析。结果表明:... 天然漆酶的催化活性和稳定性易受外界环境因素的不良影响,受天然漆酶活性中心和电子转移的启发,利用6-巯基嘌呤与铜离子的配位反应合成一种新型漆酶模拟酶(Cu-MP),并采用SEM-EDS、BET、FTIR、XRD、XPS对其性能进行表征并分析。结果表明:Cu-MP呈珊瑚状多孔网状结构,可为催化反应提供较大的比表面积;6-MP主要通过硫和碱基氮(N7)与铜离子配位合成Cu-MP。催化机理推测,模拟酶Cu-MP通过铜离子从底物获取电子后,按照S-C_(6)-C_(5)-N_(7)通道实现电子转移;与相同质量浓度下的天然漆酶相比,Cu-MP对底物的亲和力更佳,其最大反应速度v_(max)是天然漆酶的4.7倍;在25℃下储存7 d后,Cu-MP的酶活保留率达84.03%;经过9轮循环利用,酶活保留率在70%以上;甚至在高盐或有机溶液中,Cu-MP仍能保持相对稳定的催化活性。因此,Cu-MP可以取代天然漆酶,尤其在一些极端条件下,用于处理酚类等环境污染物,是一种具有发展和应用前景的环境催化剂。 展开更多
关键词 天然漆酶 铜基漆酶模拟酶 Cu-mp 催化机理 酚类污染物
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非特殊型浸润性乳腺癌新辅助化疗后RCB分级与MP分级在预后分析中的比较研究
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作者 葛志文 连渊娥 +1 位作者 郑巧灵 杨映红 《临床与实验病理学杂志》 CAS 北大核心 2024年第9期947-954,共8页
目的 分析新辅助化疗后非特殊型浸润性乳腺癌患者的临床病理学相关因素对残余肿瘤负荷(residual cancer burden, RCB)分级系统和Miller-Payne(MP)分级系统的影响,并探讨两种分级系统对患者生存的预测价值。方法 收集术前穿刺确诊为非特... 目的 分析新辅助化疗后非特殊型浸润性乳腺癌患者的临床病理学相关因素对残余肿瘤负荷(residual cancer burden, RCB)分级系统和Miller-Payne(MP)分级系统的影响,并探讨两种分级系统对患者生存的预测价值。方法 收集术前穿刺确诊为非特殊型浸润性乳腺癌,并施行新辅助化疗的177例患者临床资料进行回顾性分析。分别研究RCB分级系统及MP分级系统与无病生存期(disease-free survival, DFS)和总生存期(overall survival, OS)的关系,分析比较两者对预后判断的价值。结果 RCB分级与月经状态、治疗前组织学分级、治疗后淋巴结转移情况相关,而MP分级与治疗前组织学分级、治疗后淋巴结转移情况、治疗前分子分型相关。通过观察复发与生存的ROC曲线图,比较曲线下面积(AUC),可以得出RCB分级系统对于复发和生存的预测优于MP分级系统。单因素及多因素生存分析显示治疗前临床分期、治疗后淋巴结转移情况及RCB分级为DFS的独立影响因素,治疗前临床分期、治疗前分子分型、RCB分级为OS的独立影响因素,而MP分级不是DFS及OS的独立影响因素。结论 RCB分级系统较MP分级系统对患者生存的预测价值更高,推荐将RCB分级评估系统作为非特殊型浸润性乳腺癌新辅助化疗后的首选评估体系。 展开更多
关键词 乳腺肿瘤 新辅助化疗 mp分级 RCB分级
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Early methylprednisolone impact treatment for sensory and motor function recovery in patients with acute spinal cord injury A self-control study
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作者 Chao Zhuang Liming Wang Yan Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2008年第5期577-580,共4页
BACKGROUND: For the treatment of spinal cord injury, any pathological changes of the injured tissue should be primarily corrected or reversed. Any remaining fibrous function and neurons with intact structure should b... BACKGROUND: For the treatment of spinal cord injury, any pathological changes of the injured tissue should be primarily corrected or reversed. Any remaining fibrous function and neurons with intact structure should be retained, and the toxic substances caused by ischemia-hypoxia following spinal cord injury, should be eliminated to create a favorable environment that would promote neural functional recovery. OBJECTIVE: This study was designed to investigate the effects of the impact of early methylprednisolone-treatment on the sensory and motor function recovery in patients with acute spinal cord injury. DESIGN: A self-control observation. SETTING: Department of Spine Surgery, First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu Province, China. PARTICIPANTS: Forty-three patients with acute spinal cord injury were admitted to the Department of Spine Surgery, First Affiliated Hospital of Nanjing Medical University, between October 2005 and September 2007. These patients were recruited for the present study. The patients comprised 33 males and 10 females, and all met with the inclusive criteria namely, the time between suffering from acute spinal cord injury and receiving treatment was less than or equal to eight hours. METHODS: According to the protocol determined by the State Second Conference of Acute Spinal Cord Injury of USA, all patients received the drop-wise administration of a 30-mg/kg dose of methylprednisolone (H200040339, 500 mg/bottle, Pharmacia N.V/S.A, Belgium) for 15 minutes within 8 hours post injury. After a 45-minute interval, methylprednisolone was administered at 5.4 mg/kg/h for 23 hours. MAIN OUTCOME MEASURES: Prior to and post treatment, acupuncture sense and light touch scoring were performed at 28 dermatomic area key points, including occipital tuberosity and supraclavicular fossa. At the same time, motor scoring of key muscles among 10 pairs of sarcomeres was also performed. RESULTS: All 43 patients participated in the final analysis. There was no significant difference of sensory and motor scores in patients with complete acute spinal cord injury between prior to and post methylprednisolone impact treatment (P 〉 0.05). The motor score was significantly decreased in patients with incomplete acute spinal cord injury post methylprednisolone impact treatment (P 〈 0.01 ). CONCLUSION: Early methylprednisolone impact may improve the motor function of patients with incomplete acute spinal cord injury. However, it has no influences on patients with complete acute spinal cord injury. 展开更多
关键词 methylprednisolone acute spinal cord injury sensory and motor function
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Effect of Intravenous Methylprednisolone on the Signs &Symptoms of Graves’ Ophthalmopathy
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作者 Muhammad Shah Alam A. B. M. Kamrul-Hasan +2 位作者 Syeda Tanzina Kalam Ajit Kumar Paul Shahjada Selim 《Open Journal of Endocrine and Metabolic Diseases》 2019年第9期95-101,共7页
Background: Graves’ ophthalmopathy (GO) is the most frequent extrathyroidal manifestation of Graves’ disease (GD). The effect of intravenous methylprednisolone on the signs and symptoms of GO has not been evaluated ... Background: Graves’ ophthalmopathy (GO) is the most frequent extrathyroidal manifestation of Graves’ disease (GD). The effect of intravenous methylprednisolone on the signs and symptoms of GO has not been evaluated in the Bangladeshi population. Objective: To observe the effect of intravenous methylprednisolone in active Graves’ ophthalmopathy. Materials/Methods: This prospective study conducted in a tertiary hospital of Bangladesh from May 2009 to November 2010 included 30 patients having moderate to severe ophthalmopathy. In addition to the clinical activity score (CAS), eye involvement was assessed by using the “NOSPECS” scoring system. Results: The mean (±SD) age of the patients was 38.1 ± 10.6 years and male-female ratio was 1.2:1. NOSPECS eye findings before treatment and during the final (3rd) visit of the patients were observed. It was found that lid retraction or lid lag was improved in 21 (70%) of the patients during the final visit. All of the patients had soft tissue swelling initially and all of them improved at the final visit. Bilateral proptosis was present in 19 patients before treatment and improved in 12 (62%) patients during the final visit. Right eye proptosis was present in 9 patients before treatment and improved in 5 (60%) patients during final visit. Extraocular muscle involvement (Diplopia) was present in 15 patients before treatment but improved in 13 (86.0%) patients during the final visit. A significant number of subjects showed significant improvement in all of the NOSPECS eye findings (except unilateral right eye proptosis) during the final visit;all had inactive GO (CAS Conclusion: Intravenous methylprednisolone appears to be an effective treatment option for active Graves’ ophthalmopathy. 展开更多
关键词 Graves’ OPHTHALMOPATHY NOSPECS methylprednisolone
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Intravenous immunoglobulin accompanied with high-dose methylprednisolone therapy for 17 children with anti-N-methyl-D-aspartate receptor encephalitis:Clinic and nursing
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作者 Huihan Zhao Yunli Han +4 位作者 Yu He Huiqiao Huang Qin Wei Pengpeng Wang Yanping Ying 《International Journal of Nursing Sciences》 2016年第4期385-389,共5页
Objective:An increasing number of pediatric patients are being diagnosed with anti-N-methyl-Daspartate receptor(NMDAR)encephalitis,whose treatment requires immunotherapy through nursing interventions.This study aimed ... Objective:An increasing number of pediatric patients are being diagnosed with anti-N-methyl-Daspartate receptor(NMDAR)encephalitis,whose treatment requires immunotherapy through nursing interventions.This study aimed to analyze the clinical features and long-term prognosis of pediatric anti-NMDAR encephalitis and to gather nursing experiences of immunotherapy.Methods:Seventeen children diagnosed with anti-NMDAR encephalitis were admitted to the pediatric department.They were subjected to a therapy of intravenous immunoglobulin(IVIG)accompanied with high-dose methylprednisolone(HDMP).Multidisciplinary cooperation and intensive care were used to manage them.The effects of nursing intervention and therapy were repeatedly assessed and analyzed throughout the course of treatment and recovery.Results:None of the patients manifested adverse drug reaction(ADR)during IVIG administration.At the first administration of HDMP,ADRs were promptly and efficiently treated in four patients(24%;i.e.,one case each of hyperglycosemia,hypertension,aggravated symptoms,and gastrointestinal bleed).Two patients underwent rehabilitation,and six patients received hyperbaric oxygenation during hospitalization.Nine patients with indwelling gastric tubes experienced four times of unplanned extubation.Hospital stay ranged from 11 days to 59 days,with the mean duration of 26 days.Discharge evaluation revealed that 16 patients who scored 0e2 on the modified Rankin scale presented obvious remission,and one patient who had a mRS score of 4 exhibited less improvement.The mRS scores of hospitalization,discharge,and six-month follow-up displayed statistically significant differences.Conclusions:Nursing interventions of immunotherapy ensures the security of IVIG administration.Multidisciplinary cooperation promotes remission.Our findings can serve as reference for healthcare teams. 展开更多
关键词 Anti-N-methyl-D-aspartate receptor ENCEPHALITIS IMMUNOGLOBULIN methylprednisolone Immunotherapy NURSING Multidisciplinary
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MP妊高征监测系统联合PLGF和PI对子痫前期的预测价值
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作者 张丽冉 赵延华 《天津医药》 CAS 2024年第3期306-310,共5页
目的通过妊娠高血压综合征监测系统测定妊高征风险评级和胎盘生长因子(PLGF)水平,以及胎儿颈项透明层厚度(NT)检查时测得的子宫动脉搏动指数(PI)的联合应用,建立对子痫前期的临床预测模型。方法选择子痫前期患者24例作为病例组,随机抽... 目的通过妊娠高血压综合征监测系统测定妊高征风险评级和胎盘生长因子(PLGF)水平,以及胎儿颈项透明层厚度(NT)检查时测得的子宫动脉搏动指数(PI)的联合应用,建立对子痫前期的临床预测模型。方法选择子痫前期患者24例作为病例组,随机抽取同期有良好妊娠结局的孕妇95例作为对照组,收集2组在孕11~14周免疫荧光定量检测法测定的血清PLGF水平,子宫动脉PI,孕11~20周MP妊高征监测系统风险评级(MP风险)及其他相关数据,记录产前体质量指数(BMI)、年龄、孕次、分娩方式、新生儿出生体质量及Apgar评分。结果单因素Logistic回归分析结果显示,BMI、年龄、PI、MP风险、PLGF是出现不良结局的影响因素。多因素回归分析结果显示高PI、MP中高风险和PLGF<12是影响出现不良结局的独立危险因素,建立的PE预测模型为logit(P)=-15.767+0.020×PI+0.072×MP风险+0.181×PLGF,ROC曲线下面积(AUC)为0.883,特异度为0.816,敏感度为0.846。结论联合PI、MP风险、PLGF建立子痫前期临床预测模型具有一定的价值,且其联合预测价值高于单独应用。 展开更多
关键词 先兆子痫 模型 统计学 高血压 妊娠性 胎盘生长因子 mp妊高征监测系统 搏动指数
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基于3MP理论框架优化烟草“四虫一剂”综合防控体系的思考
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作者 李皓 陆歆 +6 位作者 ISMOILOV Khasan 孟玉芳 桑文 王兴民 杨海林 王明慧 韩鹏 《环境昆虫学报》 CSCD 北大核心 2024年第6期1261-1270,共10页
烟草Nicotiana tabacum L.是我国重要的经济作物之一。当前,我国烟草产业正处于向绿色、生态转型升级的关键阶段,而病虫害防治是保障烟草行业转型升级的关键环节。以有害生物综合治理(Integrated Pest Management,IPM)框架为基础的烟草... 烟草Nicotiana tabacum L.是我国重要的经济作物之一。当前,我国烟草产业正处于向绿色、生态转型升级的关键阶段,而病虫害防治是保障烟草行业转型升级的关键环节。以有害生物综合治理(Integrated Pest Management,IPM)框架为基础的烟草“四虫一剂”综合防控体系应运而生。该体系包括科学组合利用捕食螨(胡瓜新小绥螨Neoseiulus cucumeris Oudermans)、烟蚜茧蜂Aphidius gifuensis Ashmead、夜蛾黑卵蜂Telenomus remus Nixon和叉角厉蝽Cantheconidae furcellata Wolff防治多种烟田害虫,以及利用烟草内源抗病毒制剂防治烟草花叶病毒病,是目前云南烟区重点推广的绿色防控技术体系。为了解决实际生产中IPM框架内各单一防控技术在治理多种害虫时发生的“低协同度”和“低覆盖度”的问题,我们前期提出了“多害虫多维治理”(Multi-Dimensional Management of Multiple Pests,3MP)理论框架。本研究基于3MP理论框架,就如何提高烟草“四虫一剂”体系中各绿色防控技术的集成度展开讨论,旨在为优化“四虫一剂”防控体系提供参考思路。 展开更多
关键词 烟草 “四虫一剂” 3mp理论框架 IPM
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一种具有低泄漏电流和高浪涌电流能力的1200 V/20 A SiC MPS
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作者 易波 徐艺 +5 位作者 马克强 王思亮 蒋兴莉 胡强 程骏骥 杨洪强 《微电子学》 CAS 北大核心 2024年第1期141-144,共4页
通过离子注入优化,成功研制了一款六角形元胞设计的1 200 V/20 A的具有低泄漏电流和高浪涌电流能力的SiC MPS芯片。在25℃和175℃下的测试结果表明,导通压降VF分别为1.48 V和2.03 V;归功于优化的离子注入和元胞设计,1 200 V耐压时,肖特... 通过离子注入优化,成功研制了一款六角形元胞设计的1 200 V/20 A的具有低泄漏电流和高浪涌电流能力的SiC MPS芯片。在25℃和175℃下的测试结果表明,导通压降VF分别为1.48 V和2.03 V;归功于优化的离子注入和元胞设计,1 200 V耐压时,肖特基界面的最强电场强度仅为1.25 MV/cm。研制的MPS的泄漏电流仅为4.3μA(@25℃)和13.7μA(@175℃)。并且25℃和150℃下测试的浪涌电流高达258 A和252 A,约为额定电流的13倍。 展开更多
关键词 SiC mpS 泄漏电流 高温漏电 浪涌电流能力
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基于A1050板料的MP4前壳成形模设计
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作者 毛建冬 肖国华 +4 位作者 李亚峰 余健 李兴秀 徐生 杨少增 《模具工业》 2024年第4期14-20,共7页
针对MP4前壳生产要求,设计了12副模具用于批量生产,模具设计了4种机构成形困难特征部位,侧冲切滑块机构用于去除壳体直壁局部区域的毛刺,侧面刮切机构用于切除孔边直壁的局部,卡扣弯曲机构用于成形卡扣的90°弯曲,二次成形滑块机构... 针对MP4前壳生产要求,设计了12副模具用于批量生产,模具设计了4种机构成形困难特征部位,侧冲切滑块机构用于去除壳体直壁局部区域的毛刺,侧面刮切机构用于切除孔边直壁的局部,卡扣弯曲机构用于成形卡扣的90°弯曲,二次成形滑块机构用于卡扣的精修和侧面冲孔。成形工艺工序布置合理,成品合格率达到98%,模具结构简单实用,制造成本低,相当于级进模方案成本的72%。针对成形困难特征设计的机构动作可靠、实用性好,能为成形同类制件模具的结构设计提供借鉴。 展开更多
关键词 mp4前壳 成形工艺 滑块机构 弯曲 二次成形
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预氧化处理对MP35N合金高温氧化行为的影响
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作者 刘鲁 刘亚 +2 位作者 吴长军 吴昱锋 苏旭平 《表面技术》 EI CAS CSCD 北大核心 2024年第2期60-70,共11页
目的 探索并优化合金成分、工艺以获得致密稳定的预氧化膜,提高合金抗氧化能力。方法 利用非自耗真空电弧炉熔炼合金,在真空容器中加热金属及其氧化物粉末获得平衡氧压。通过莱茵装置进行预氧化实验。通过FactSage计算Co-Ni-Cr-Mo-Al-S... 目的 探索并优化合金成分、工艺以获得致密稳定的预氧化膜,提高合金抗氧化能力。方法 利用非自耗真空电弧炉熔炼合金,在真空容器中加热金属及其氧化物粉末获得平衡氧压。通过莱茵装置进行预氧化实验。通过FactSage计算Co-Ni-Cr-Mo-Al-Si体系的合金组织相图及其氧化相图,利用X射线衍射(XRD)和扫描电子显微镜对预氧化的试样进行物相分析。结果 在1000℃、10^(–17)atm氧压下预氧化,未含Si的MP35N合金表面出现Cr_(2)O_(3)氧化物;随着Si添加量的增加,表面氧化物变为(Al,Cr)_(2)O_(3),以Cr_(2)O_(3)为主,内氧化物为Al_(2)O_(3);当Si含量(质量分数)为3%时,内部形成了近乎连续的带状Al_(2)O_(3)氧化膜。在1 000℃、10^(–25) atm氧压下,合金表面形成连续的Al_(2)O_(3)膜;在1 000℃、10^(–17) atm氧压下,Co-Ni-20Cr-10Mo-4Al-1Si合金预氧化后的外氧化膜为Cr_(2)O_(3),内氧化物为Al_(2)O_(3);随着氧压的提高,在空气气氛下合金表面生成尖晶石相氧化物。在1 000℃、10^(–17)atm氧压下预氧化1、5、10h,Co-Ni-20Cr-10Mo-4Al-1Si合金表面外氧化膜为Cr_(2)O_(3),内氧化物为Al_(2)O_(3),随着时间延长至20 h,合金表面形成连续的Al_(2)O_(3)膜。结论 随着Si添加量的增加,Al元素的活度不断升高,从而提高了Al_(2)O_(3)的形成驱动力,提升了Al元素的扩散系数,有更多的Al元素扩散至合金表层,有利于Al元素的选择性氧化。预氧化氧压的降低和氧化时间的延长,有利于保护性外氧化Al_(2)O_(3)膜形成,可有效提高合金的抗高温氧化性能。 展开更多
关键词 mp35N Co-Ni-20Cr合金 预氧化 Al_(2)O_(3)氧化膜 氧化机制 表面改性
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具有沟槽氧化物和P-屏蔽层的4H-SiC MPS的设计与仿真
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作者 蔡艺 汪再兴 +2 位作者 姜佳池 王林昌 党超 《电子元件与材料》 CAS 北大核心 2024年第9期1063-1070,共8页
利用TCAD仿真研究了一种具有沟槽氧化物和P-屏蔽层结构的新型4H-SiC TP-MPS二极管。通过在传统MPS中引入沟槽氧化物和P-屏蔽层,能够有效地抑制器件的迅回效应和改善其反向恢复特性。分别仿真了漂移区掺杂浓度、P-区深度及SiO2厚度等关... 利用TCAD仿真研究了一种具有沟槽氧化物和P-屏蔽层结构的新型4H-SiC TP-MPS二极管。通过在传统MPS中引入沟槽氧化物和P-屏蔽层,能够有效地抑制器件的迅回效应和改善其反向恢复特性。分别仿真了漂移区掺杂浓度、P-区深度及SiO2厚度等关键参数对迅回效应和反向恢复特性的影响。研究结果表明:增加金属功函数、P-区厚度和SiO2厚度,以及减小漂移区掺杂浓度,均可以有效抑制MPS二极管的迅回效应;而增加SiO2厚度、减小P-区厚度和漂移区掺杂浓度均可以改善其反向恢复特性。对比传统MPS结构,TP-MPS结构在SiO2厚度为2.5μm、P-区厚度为2μm、漂移区掺杂浓度为4×10^(15)cm^(-3)的条件下,转折电压降低了34.8%,反向恢复峰值电流降低了23.5%,反向恢复软度因子增加了80%。TP-MPS二极管对迅回效应有明显抑制作用,并且其反向恢复特性得到改善。 展开更多
关键词 4H-SIC mpS二极管 迅回效应 转折电压 反向恢复特性
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Methylprednisolone injection following the surgical extraction of impacted lower third molars:A split-mouth study
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作者 Jorge Chaurand-Lara Jose Alfredo Facio-Umana 《Open Journal of Stomatology》 2013年第2期192-196,共5页
Purpose: The purpose of the present study was to compare the effect of intramuscular masseter administration of methylprednisolone using a split-mouth design, as a single 20-mg dose, after removal of impacted lower th... Purpose: The purpose of the present study was to compare the effect of intramuscular masseter administration of methylprednisolone using a split-mouth design, as a single 20-mg dose, after removal of impacted lower third molars. Patients and Methods: A non-blind, cross-over, comparative, non-randomized, clinical trial was planned. The sample was composed of 32 patients requiring extraction under local anesthesia of two lower bony impacted mandibular third molars. The difficulty of extraction was similar in all cases. The patients received 20 mg of methylprednisolone injected into the masseter muscle via the intrabuccal approach, immediately after suturing of the surgical wound on the right side. The left side received no intramuscular corticoid. Evaluations were made of postoperative pain and swelling. Results: A total of 32 subjects requiring surgical removal of two impacted mandibular third molars under local anesthesia were included in the present study. The patients administered methylprednisolone showed superior results after surgery in terms of pain and facial swelling parameters using self-evaluation, with statistically significant differences versus the control-side (p < 0.05). The results obtained show that 20 mg of methylprednisolone injected into the masseter muscle in the immediate postoperative period reduces swelling and pain. Conclusions: Injection of methylprednisolone is an effective therapeutic strategy to reduce swelling and pain after surgical removal of impacted lower third molars. It offers a simple, safe, painless, noninvasive, and cost effective therapeutic option for moderate and severe cases. 展开更多
关键词 methylprednisolone Third Molar Surgery Split-Mouth Study
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“公安学+MP”双学位高层次警务人才培养模式研究 被引量:1
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作者 张拓 《中国人民警察大学学报》 2024年第3期92-96,共5页
在总体国家安全观背景下,法治人才队伍建设急需大量能指挥、懂技术、会管理的复合型高层次警务人才,突出德法兼修的培养理念,创新警务人才培养模式迫在眉睫。以《关于坚持德法兼修实施卓越法治人才教育培养计划2.0的意见》对法治公安队... 在总体国家安全观背景下,法治人才队伍建设急需大量能指挥、懂技术、会管理的复合型高层次警务人才,突出德法兼修的培养理念,创新警务人才培养模式迫在眉睫。以《关于坚持德法兼修实施卓越法治人才教育培养计划2.0的意见》对法治公安队伍建设提出的更高要求为引导,梳理总结公安学和警务学科研究生教育基本情况,从“公安学+MP”双学位项目实施的可行性与理论基础入手,围绕构建培养框架、优化课程体系、推进产学研合作、建立质量保障体系等举措,探究双学位项目的实施路径,以期推动公安院校“指技管”一体高层次警务人才培养,破解多学科交叉融合关键难点问题。 展开更多
关键词 公安学 mp 双学位 警务人才 培养模式
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基于MPS方法的固定半潜式平台波浪爬升数值模拟
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作者 吴萌萌 王尼娜 万德成 《海洋工程》 CSCD 北大核心 2024年第4期44-56,共13页
在波浪与半潜式平台相互作用的情况下,波浪会沿着平台立柱爬升,并对平台立柱产生砰击作用。在极端情况下,波浪甚至可能砰击至平台下甲板,严重影响平台的安全。因此,对于半潜式平台设计来说,准确预测平台在波浪中的波浪爬升和砰击效应具... 在波浪与半潜式平台相互作用的情况下,波浪会沿着平台立柱爬升,并对平台立柱产生砰击作用。在极端情况下,波浪甚至可能砰击至平台下甲板,严重影响平台的安全。因此,对于半潜式平台设计来说,准确预测平台在波浪中的波浪爬升和砰击效应具有重要意义。采用无网格粒子法求解器MPSGPU-SJTU对波浪作用下的固定半潜式平台问题进行了数值研究,将MPS(moving particle semi-implicit)方法与GPU(graphics processing unit)并行加速技术相结合,并将其应用于规则波作用下的固定半潜式平台波浪爬升与波浪砰击问题的数值模拟。3种不同波高的规则波波浪被应用于半潜式平台数值模拟中,随着波高的增加,平台下甲板更多区域受到了波浪的砰击,同时平台设置的测压点处压力峰值也随之增大。 展开更多
关键词 mpS方法 固定半潜式平台 GPU并行加速技术 波浪爬升 波浪砰击
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血清tRNA衍生片段tRF-17-79MP9PP的表达及与乳腺癌患者预后的相关性
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作者 莫冬萍 杨子龙 王承霞 《临床检验杂志》 CAS 2024年第7期488-491,共4页
目的检测乳腺癌患者血清tRNA衍生物tRF-17-79MP9PP(tRF-17)的表达水平,并分析其与患者预后的相关性。方法选取2016年6月至2019年12月本院收治并确诊的70例乳腺癌患者及25例健康人对照组的血清标本,记录患者的临床资料和数据。采用实时... 目的检测乳腺癌患者血清tRNA衍生物tRF-17-79MP9PP(tRF-17)的表达水平,并分析其与患者预后的相关性。方法选取2016年6月至2019年12月本院收治并确诊的70例乳腺癌患者及25例健康人对照组的血清标本,记录患者的临床资料和数据。采用实时荧光定量PCR(qRT-PCR)检测两组血清tRF-17的表达水平;绘制ROC曲线并分析tRF-17对乳腺癌的临床筛查价值;采用Spearman相关分析tRF-17与血液炎症指标以及肿瘤标志物的相关性,随访截止日期为2023年4月,使用单因素和多因素COX回归分析乳腺癌预后不良的影响因素。结果与健康人对照组的14.09(5.14,21.34)相比,乳腺癌患者血清tRF-17的表达水平[3.99(0.70,10.46)]显著降低,差异有统计学意义(Z=-3.575,P<0.01);其筛查乳腺癌的ROC曲线下面积(AUCROC)为0.742(95%CI:0.635~0.849,P<0.01)。tRF-17高表达组乳腺癌患者的平均生存时间显著高于低表达组(75.97个月vs 56.06个月,log-rank P<0.01)。COX比例风险模型分析提示,淋巴结转移和血清tRF-17表达水平均是影响患者预后的独立危险因素(HR=1.723,95%CI:1.084~2.739,P<0.05;HR=0.189,95%CI:0.041~0.862,P<0.05)。结论乳腺癌患者血清tRF-17呈低表达,其表达水平是影响乳腺癌患者预后的独立危险因素,或可成为一种评估患者预后的生物学标志物。 展开更多
关键词 tRNA衍生片段 tRF-17-79mp9PP 乳腺癌 预后 生物学标志物
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