离岸集装箱码头新装卸工艺模式下陆域集疏运堆场堆存空间分配     

杨晓斌  余思勤  沈一帆 《上海海事大学学报》2020,41(4):8-14

离岸集装箱码头因其岛屿面积限制，难以通过扩建码头内部堆场增加吞吐能力。为解决这个问题，提出一种离岸集装箱码头新装卸工艺模式。新装卸工艺模式是通过在离岸集装箱码头附近的陆域地带建设陆域集疏运堆场,与离岸集装箱码头进行协同装卸作业的模式。陆域集疏运堆场堆存空间分配的目标是满足离岸集装箱码头装卸作业预翻倒要求;单批次输送集装箱的量受到陆岛运输最大通行能力限制。根据上述目标与特点，构建新装卸工艺模式下陆域集疏运堆场堆存空间分配模型，并设计蒙特卡洛树搜索算法进行求解。通过算例分析验证模型的有效性。结果表明该方法能够满足陆域集疏运堆场堆存空间分配需求并提高离岸集装箱码头的吞吐能力。  相似文献   

Effects of periodic carbohydrate ingestion on endurance and cognitive performances during a 40-km cycling time-trial under normobaric hypoxia in well-trained triathletes     

Yi-Hung Liao  Toby Mündel  Yan-Ting Yang  Chen-Chan Wei  Shiow-Chwen Tsai 《Journal of sports sciences》2019,37(16):1805-1815

The purpose of this study was to examine CHO ingestion on a cognitive task using a field-simulated time-trial (TT) under hypoxia in well-trained triathletes. Ten male triathletes (age: 22.1 ± 1.1 years; VO₂max: 59.4 ± 1.4 ml/kg/min) participated in this double-blind/crossover/counter-balanced design study. Participants completed 3 TT trials: 1) normoxic placebo (NPLA; FiO₂ = 20.9%), 2) hypoxic placebo (HPLA; FiO₂ = 16.3%), and 3) hypoxic CHO (HCHO; 6% CHO provided as 2 ml/kg/15 min; FiO₂ = 16.3%). During the TT, physiological responses (SpO₂, HR, RPE, and blood glucose/lactate), cognitive performance, and cerebral haemodynamics were measured. Hypoxia reduced TT performance by ~3.5–4% (p < 0.05), but CHO did not affect TT performance under hypoxia. For the cognitive task, CHO slightly preserved exercise-induced cognitive reaction speed but did not affect response accuracy during hypoxic exercise. However, CHO did not preserve the decreased Hb-Diff (cerebral blood flow, CBF) and increased HHb in the prefrontal lobe (p < 0.05) during hypoxic exercise, and CHO failed to preserve hypoxia-suppressed prefrontal CBF and tissue oxygen saturation. In conclusion, the present study demonstrates that CHO is effective in sustaining reaction speed for a cognitive task but not promoting TT performance during hypoxic exercise, which would be important for strategy-/decision-making when athletes compete at moderate high-altitude.  相似文献   

Physiological responses in different intensities of resistance exercise – Critical load and the effects of aging process     

Vivian Maria Arakelian  Cássia da Luz Goulart  Renata Gonçalves Mendes  Nuno Manoel de Sousa  Renata Trimer  Solange Guizilini 《Journal of sports sciences》2019,37(12):1420-1428

Aim was to identify critical load (CL) in young and elderly apparently healthy male cohorts. To contrast the metabolic, cardiovascular and perceptual responses on CL according to age. We evaluated 12 young (23 ± 3 years) and 10 elderly (70 ± 2 years) apparently healthy active males, who underwent: (1) 1 repetition maximum (1RM) test on a 45° Leg Press; (2) on different days, three high-intensity resistance exercise constant load tests (60%, 75% and 90% 1RM) until fatigue (Tlim). Absolute values of both the CL asymptote and curvature constant (kg) were significantly lower in elderly subjects (P < 0.05). In contrast, elderly subjects demonstrated a significantly higher number of repetitions at CL when compared with young subjects (P < 0.05). As expected, oxygen uptake (VO₂) and heart rate (HR) during maximal aerobic exercise testing were significantly reduced in older subjects. However, percent-predicted aerobic capacity were higher in older subjects (P < 0.05). In addition, blood lactate ([La^?]) corrected to Tlim and rating of perceived exertion values were greater in younger subjects at all intensities (P < 0.05). These findings, despite reduced force production in older subjects, endurance-related parameters are well preserved according to age-adjusted percent-predicted values in apparently healthy males.  相似文献   

NiCo_2O_4纳米结构阵列的水热合成与氧析出特性研究     

陈传胜  张作胜  陈伟杰  乔浏 《安徽职业技术学院学报》2020,(1):16-19,41

钴酸镍纳米材料具有良好的电催化氧析出反应(Oxygen Evolution Reaction,OER)活性,是一种很有发展潜力的非贵金属电催化材料。文章以碳纤维纸为基底,采用水热合成的方法对纳米结构钴酸镍的生长进行了系统的研究,分别考察了生长温度、前驱体浓度和配比、生长时间对产物的形貌、尺寸、物相结构、OER电化学性能的影响,通过对比分析后发现在生长温度100℃、生长时间5h、镍钴比为2:1时所获得的多孔片状钴酸镍纳米结构具有最佳的OER特性。  相似文献   

一维同核化学位移相关谱的研究及其应用     

许小平 《科技通报》1994,10(2):105-105

从理论上分析研究了一维同核化学位移相关谱，并采用单片微处理机技术，首次在ＪＥＯＬＦＸ９０Ｑ核磁共振波谱仪上建立了一维同核化学位移相关谱方法，成功地测定了一些化合物的一维同核化学位移相关谱，得到了较好的结果。  相似文献   

Protective Role of <Emphasis Type="SmallCaps">l</Emphasis>-Arginine Against Free-Radical Mediated Oxidative Damage in Patients with Unstable Angina     

Tripathi P  Chandra M  Misra MK 《Indian journal of clinical biochemistry : IJCB》2010,25(3):302-306

Unstable angina is a critical condition of heart resulting from narrowing of vessels supplying blood to heart. Ischemia of the myocardium leads to oxidative stress and severe tissue damage. The objective of the present study was to determine the effect of l-arginine administration on the oxidant–antioxidant homeostasis which otherwise gets imbalanced in patients with cardiovascular diseases. The results obtained, show improvement in the oxidant–antioxidant levels of the subjects upon incorporation of l-arginine. Our findings suggest that supplementation of l-arginine along with regular anti-anginal therapy may be beneficial to the patients of unstable angina.  相似文献   

轴向柱塞泵流体噪声的机理分析   总被引：2，自引：0，他引：2  

方孝荣  杜巧连  陈海荣 《科技通报》2002,18(5):424-427

以降低轴向柱塞泵流体噪声为目的，围绕轴向柱塞泵的柱塞数和轴向柱塞泵配油盘结构对产生流体噪声的机理进行了理论分析，并对降低轴向柱塞泵流体噪声的措施进行了试验。试验研究表明：对轴向柱塞泵配油盘结构进行优化设计，使柱塞腔内高压油与低压油切换时避免高、低压油突然串通而造成的压力冲击所产生的噪声，是降低轴向柱塞泵流体噪声的一条有效途径。  相似文献   

烟雾吸入伤早期氧化与抗氧化动态平衡变化的实验研究   总被引：1，自引：0，他引：1  

谢尔凡  杨宗城 《科技通报》1997,13(1):39-43

采用大鼠烟雾吸入伤模型，动态观察了伤后血浆、支气管肺泡灌洗液（ＢＡＬＦ）和肺组织中超氧化物歧化酶（ＳＯＤ）活性、丙二醛（ＭＤＡ）和共轭二烯（ＣＤ）含量的变化，辅以动脉血气分析、肺水量测定、ＢＡＬＦ中白细胞分类计数和病理检查．结果发现，伤后动物出现急性呼吸衰竭和严重肺水肿，肺内大量炎细胞聚集浸润；血浆、ＢＡＬＦ及肺组织中ＳＯＤ活性明显降低，ＣＤ和ＭＤＡ含量显著增加，ＭＤＡ／ＳＯＤ比值亦明显增高，且与ＢＡＬＦ中中性粒细胞数增加显著相关，提示氧化与抗氧化平衡失调可能在急性烟雾吸入性肺损伤的发生发展中起重要作用  相似文献   

Dietary restriction (DR) and its advantages     

M. N. Astagimath  Shrinivas B. Rao 《Indian journal of clinical biochemistry : IJCB》2004,19(1):1-5

Dietary restriction (DR) also called dietary control or calorie restriction is reported to have many advantages with regard to human health. It leads to suppression of obesity, mitigates free radicals and increases available antioxidants which are accounted for extending the life span of individuals. DR is also reported to induce synthesis of heat shock proteins in animals as a control mechanism against stress. Further, it is known to play a significant role in decreasing toxicity and lethality due to a variety of toxic chemicals and drugs by stimulating tissue repair damaged by the toxicants leading to restoration of intact organ and its functions. Moreover, extensive work done on animals indicate DR has an important role in suppressing certain types of cancer. In this review an effort is made to highlight the various advantages of DR from the point of human health perspective.  相似文献   

基于LabView的脉冲核磁共振实验     

阙立志  倪晓武 《实验室研究与探索》2008,27(3):51-54

针对现有脉冲核磁共振实验用示波器显示和测量实验数据精度差的缺点,提出利用计算机声卡采集实验数据,用LabView软件开发实验数据采集及分析系统,具有测量精度高、操作简单、智能化分析的特点。  相似文献