(A) Study on the Simulation of the Fuel Injection System in a Large Low-speed Marine Diesel Engine

It has been a major research to improve the performance and reliability of diesel engine, since internal combustion engine has been invented originally. However, recently much of these researches are focused on the reduction of exhaust emission for environmental pollution protection with the concerns of the low fuel consumption rate. The charactristics of fuel injection system have a strong influence on the air-fuel mixing process and engine output, thermal efficiency, durability, noise, and exhaust emissions. The performance and exhaust emission of diesel engine is related to the fuel injection rate and injection pressure, injection duration. Combustion in diesel engine is mainly governed by characteristics of fuel injection. In this study, a simulation program was developed, which could simulate a fuel injection system for low-speed marine diesel engine. The fuel injection system was composed of fuel injection pump, high pressure pipe and fuel injection valve. The unsteady flow in the high pressure injection pipe was analyzed by the method of characteristics, considering cavitation and variation of fuel density and bulk modulus. It was assured that the simulation results agree well with experimental results of injection pressure and quantity at the high pressure distributor in fuel injection system for the training ship "M/V Hannara". And the effects of the high pressure pipe length and diameter, plunger diameter, nozzle opening pressure, nozzle hole diameter and maximum needle lift were also investigated utilizing the simulation program developed in this study.Abstract = 4 기호설명 = 6 제 1 장 서론 = 9 제 2 장 연료분사계통의 모델 = 11 2-1 연료분사계통의 작동원리 = 13 2-2 연료순환계통의 구조 = 14 2-2-1 연료펌프 = 14 2-2-2 연료노즐 = 21 2-3 쇽업소버(Shock absorber) = 22 2-4 연료캠 Control 선도 = 24 2-5 주기관 연료 순환 및 공급 선도 = 26 2-6 가변 분사시기 장치(VIT) = 28 2-7 플런저 유효행정 = 32 2-8 펌프 배럴의 연료차단구멍의 유로 단면적 = 34 2-8-1 엔진부하 중지점 이하에서의 유로 단면적 = 34 2-8-2 엔진부하 중지점 이상에서의 유로 단면적 = 37 2-9 연료노즐의 유로 단면적 = 38 제 3 장 연료분사계통의 이론 해석 = 40 3-1 연료분사계통의 기본 가정 = 40 3-2 연료분사계통의 지배 방정식 = 41 3-2-1 연료펌프 = 41 3-2-2 연료노즐 = 42 3-2-3 고압분사파이프 = 44 3-3 각 단에서의 경계조건= 49 3-4 물성치와 계수 = 52 3-5 계산 알고리즘 = 55 제 4 장 실험장치 및 실험방법 = 57 4-1 실험장치 = 57 4-2 실험방법 = 57 제 5 장 결과 및 고찰 = 60 5-1 실험결과와 계산결과의 비교 = 60 5-1-1 연료펌프의 속도변화에 의한 영향 = 60 5-2 분사계의 파라메터에 따른 시뮬레이션과 분석 = 64 5-2-1 분사파이프의 길이 및 직경 변화에 의한 영향 = 64 5-2-2 플런저 직경 변화에 의한 영향 = 67 5-2-3 연료노즐 개방압력 변화에 의한 영향 = 71 5-2-4 노즐 홀 직경 변화에 의한 영향 = 73 5-2-5 노즐 니들밸브 리프트 변화에 의한 영향 = 76 제 6 장 결론 = 78 참고문헌 = 8

现实与浪漫的唯美演绎——读冰虹小说《飘影》

冰虹是我国近年来快速成长起来的青年女作家、女诗人,发表在《山东文学》2008年第5期上的中篇小说《飘影》是她新近奉献给读者的又一篇力作

朝鮮初期雲山圖의 畫風

朝鮮初期雲山圖（靑山白雲圖）는 주로 宋代米氏의 雲林에 巨山을 折衷한 元代高克恭의 〈雲橫秀嶺圖〉와 같은 江南系雲山圖의 영향을 중심으로연구되어 왔다．그러나 한편으로 元末에 그려진 方從義의 〈雲山圖卷〉과 같은 華北系의 작품도 雲山圖라고 불리는데，本稿에서는 양식에 관계없이 이작품들이 雲山이라 불리는 이유가 米氏의 雲林이라는 모티프를 共有하기 때문이라 보았고 朝鮮初期에도 米氏의 雲林을 折衷한 다양한 畫風의 雲山圖가그려졌다는 것에 대해 考察했다．大和文華館 소장 〈雲山圖〉 6점은 高克恭系의 구도를 바탕으로 하면서도面的인 표현에 중점을 둔 高克恭의 〈雲橫秀嶺圖〉에 비해 線的인 樓閣이나樹枝法이 더해져 있는 점에서 元末雲山圖의 影響이 두드러지며 山容表現에는 元末盛懋의 간략화한 披麻皴과 胡椒點，그리고 元末의 前浙派的인 畫風 등을 折衷해서 재해석한 작품이라 보았다．南禪寺 소장 傳高然暉筆〈 雲山圖〉와〈 雪山圖〉는 그 山勢 표현이 元人筆〈靑山白雲圖〉（台北故宮博物院）에 보이는 元末의 前浙派的인 거친 筆致와유사하며，〈雲山圖〉의 높이 솟은 巨山과 雲林의 조합 등으로 볼 때 元末雲山圖의 영향을 받은 것으로 보인다．그리고 朝鮮初期에는 계절의 변화를 담은 山水畫가 유행하는데，특히 15세기 후반의 成宗期에 雲山圖와 雪山圖를함께 감상했다는 기록이 자주 보이는 점과 두 작품이 朝鮮初期山水畫에 흔히 보이는 對稱構圖를 취한 점에서 前浙派山水의 영향을 받은 15세기 후반의 朝鮮初期작품으로 보았다．九州國立博物館 소장〈 瀟湘八景圖〉의 煙寺暮鐘은 江南山水로 분류되는高克恭系의 화풍을 계승하고 있으나 細部描寫에는 15세기 후반부터 보이는朝鮮初期 특유의 短線點皴의 初期的인 특징이 보인다．그리고 이는 八景 중의 華北山水의 영향이 두드러진 작품에서도 사용되는데 이러한 점에서 短線點皴은 華北系뿐만 아니라 江南系山水에도 쓰였다는 것을 알 수 있다．또한이 그림은 煙寺暮鐘의 주요한 모티프인 樓閣이나 僧侶 등의 線的인 표현이거의 보이지 않는 것이 특이점인데，이것은 元末의 雲山圖보다는 古式인 高克恭의〈 雲橫秀嶺圖〉에 가까우며，그리고 여기에 江南山水의 廣闊한 水面表現이 折衷되어 있는 雲山圖로 이해된다．九州國立博物館 소장〈 瀟湘八景圖〉의 洞庭秋月은 華北系의 山容에 江南系의 드넓은 水面，거기에 雲林과 屋舍 등 雲山의 모티프를 折衷한 작품인데元末 張羽의“ 唐子華雲山歌” 등에서 이러한 折衷畫風을 읊고 있고，方從義의〈 雲山圖卷〉이 이러한 折衷樣式을 보이는 점에서 朝鮮初期에도 이러한 작품이 雲山圖라 불렸을 가능성이 높다는 것을 논했다．傳玉澗筆〈 雲山圖〉는 玉澗의 작품으로 전하던 것이나 近年에 朝鮮時代의작품으로 수정되었으며 本稿에서는 山稜의 點描나 山面의 線描 등이 短線點皴의 초기적인 특징이 보여 조선시대의 15세기말경의 작품이라 보았다．이상과 같이 朝鮮初期雲山圖는 다양한 화풍의 절충적인 경향이 보인다．이러한 경향은 元代復古主義에 의해 탄생한 折衷畫風인 高克恭系雲山에서 비롯한 것으로 그 思潮가 朝鮮初期畫壇에도 영향을 주어 다양하게 折衷되고 재해석된 朝鮮初期 특유의 雲山圖가 그려지게 된 것이다

Correlation between use of social software and high risk behaviors of HIV infection among MSM in Beijing

目的了解北京市男男性行为者（MSM）社交软件的使用与人类免疫缺陷病毒（HIV）感染及其影响因素的相关性,为今后干预工作提供依据。方法 2016年3—5月,由社区小组招募MSM进行问卷调查,同时进行HIV抗体检测。结果共招募215名MSM,回收有效问卷214份。214人的平均年龄为30.8岁;学历在大专及以上者占73.4%;同性恋者占72.4%;84.6%的人主要通过社交软件寻找性伴。214人中确证HIV感染5人,阳性率为2.3%。分析显示,是否使用社交软件、是否使用同性社交软件和是否使用普通人群社交软件均与HIV感染不相关。多因素分析结果显示,受教育程度高、性取向为同性恋的人更多地使用同性社交软件。63.1%被调查者自述曾经在社交软件上了解到艾滋病防治相关知识,但自述了解程度与是否通过社交软件获得相关信息不相关。结论 MSM社交软件的使用与HIV感染情况无关,也没有增加其对艾滋病知识的了解。但可以考虑改进同性社交软件功能,增加艾滋病防治知识内容,对MSM尤其是高学历、自我定位为同性恋的MSM进行艾滋病防治宣传。[Objective] To understand the correlation between the use of social software and human immunodeficiency virus（HIV）infection and its influencing factors among men who have sex with men（MSM）in Beijing,provide the basis for future intervention work.[Methods]From May to March in 2016,MSM was recruited by community groups to carry out a questionnaire survey and HIV antibody of them was detected.[Results]A total of 215 MSM were recruited and 214 valid questionnaires were recovered. The average age of the 214 MSM was 30.8 years old,73.4% had the education level in college and above,the homosexuals accounted for 72.4%,and84.6% of the respondents mainly found sexual partners through the social software. There were 5 cases of confirmed HIV infection among 214 MSM with the positive rate of 2.3%. The analysis revealed that whether the respondents use the social software,the homosexual social software and the general social software were not related to HIV infection. The results of multivariate analysis showed that people with higher educational level and homosexual orientation were more likely to use the homosexual social software. 63.1% of respondents reported that they had been obtained the knowledge of AIDS prevention and control from social software,but the understanding level was not related to whether the relevant information was obtained through social software or not.[Conclusion]The use of social software has no correlation with HIV infection among MSM,and does not increase their knowledge level of AIDS prevention and control. However,it is necessary to improve the function of the homosexual social software and increase the content of AIDS prevention and control knowledge to carry out the AIDS education among MSM,especially those with higher educational level and homosexual orientation

Ultrastructure on oogenesis of Litopenaeus vannamei

利用透射电镜研究凡纳滨对虾卵子发生过程中细胞内部结构的变化。结果显示,卵原细胞结构简单,代谢水平低,核孔稀少,通过核周池来完成核、质之间的物质交换。卵黄发生前晚期和卵黄发生初期的卵母细胞变化显著:核膜凹凸不平,核仁数量多,核孔密集,大量核仁外排物经核孔输送到卵质中;卵质中胞器极为丰富和发达,代谢活性极强。卵黄发生旺盛期是卵黄大量形成的阶段,卵质边缘还呈辐射状排列了一圈椭圆形皮质棒,细胞出现微吞饮活动并形成卵黄膜。卵黄发生晚期卵质中充满了粗大的卵黄粒和脂滴,胞器锐减。另外,探讨了卵细胞内部结构的变化和卵黄形成的关系以及皮质棒的来源与功能。The changes of the structure in oocytes during the oogenesis of Litopenaeus vannamei were studied with transmission electron microscope. The results showed that the structure was simpler and the active metabolism is lower in oogonium.The particles from the nucleus mainly passed through the perinuclear cisternae into the cytoplasm because of fewer nuclearpores. The marked changes occurred in the latter previtellogenic oocytes and the primary vitellogenic oocytes.The nuclear changes consisted of the concavo-convex nuclear membrane,many more nucleoli, numerous nuclearpores and a large amount of nucleolus granular materials penetrating nuclear membrane into cytoplasm. There were various well-developed organelles in the cytoplasm which exhibited higher synthetic activity.The yolk granules formed mainly in active vitellogenesis. At this stage,a lap spherical cortical rods appeared radializedly at the edge of the cytoplasm.Meanwhile active microphagocytosis could be seen along the ooplasma membrane while the vitellin membrane formed on the surface of vitellogenic oocytes.The mature oocytes were full of big yolk granules and lipid droplets and the number of organelles reduced quickly. The relation between the changes of the structure in oocytes and the vitellogenesis was discussed. The origin and function of the cortical rods were also discussed.福建省教育厅自然科学基金资助项目(K02091

Promoting electrocatalytic CO2 reduction to formate via sulfur-boosting water activation on indium surfaces

一般认为，H2O还原析氢反应是CO2还原反应的竞争反应，若促进H2O活化将降低CO2还原反应的法拉第效率。因此，基于该认识设计出的高CO2还原法拉第效率的催化剂常常活性低。王野课题组打破这种认识，提出H2O分子活化在CO2还原中起着重要的作用，成功合成出硫修饰In催化剂来活化H2O分子而促进CO2还原制甲酸的新方法，该催化剂在非常宽的电流密度范围内（25~100 mA cm-2），均可以维持85%以上的甲酸法拉第效率。将硫拓展至硒和碲等其它硫族元素以及将金属铟拓展至铋和锡等其它p区金属，均实现很好的促进效果，表明通过促进水的活化来提高CO2电催化还原性能具有普适性。该工作为理性设计高效的CO2还原电催化剂提供了新策略。 该研究工作实验部分主要由王野、张庆红教授指导，能源材料化学协同创新中心iChEM2016级博士生马文超、固体表面物理化学国家重点实验室高级工程师谢顺吉（共同第一作者）完成；理论计算部分由吴德印教授指导，2015级博士生张霞光（共同第一作者）完成。醇醚酯国家工程实验室高级工程师康金灿参与了部分实验表征。上海光源姜政教授和孙凡飞博士为同步辐射表征提供了支持。【Abstract】Electrocatalytic reduction of CO2 to fuels and chemicals is one of the most attractive routes for CO2 utilization. Current catalysts suffer from low faradaic efficiency of a CO2-reduction product at high current density (or reaction rate). Here, we report that a sulfur-doped indium catalyst exhibits high faradaic efficiency of formate (>85%) in a broad range of current density (25–100 mA cm−2) for electrocatalytic CO2 reduction in aqueous media. The formation rate of formate reaches 1449 μmol h−1 cm−2 with 93% faradaic efficiency, the highest value reported to date. Our studies suggest that sulfur accelerates CO2 reduction by a unique mechanism. Sulfur enhances the activation of water, forming hydrogen species that can readily react with CO2 to produce formate. The promoting effect of chalcogen modifiers can be extended to other metal catalysts. This work offers a simple and useful strategy for designing both active and selective electrocatalysts for CO2This work was supported by the National Key Research and Development Program of the Ministry of Science and Technology of China (No. 2017YFB0602201), the National Natural Science Foundation of China (Nos. 21690082, 91545203, and 21503176). We thank staff at the BL14W1 beamline of the Shanghai Synchrotron Radiation Facilities (SSRF) for assistance with the EXAFS measurements. 研究工作得到科技部重点研发计划（批准号：2017YFB0602201）和国家自然科学基金（批准号：21690082、91545203、21503176）等项目的资助

Electrocatalytic reduction of CO2 to ethylene and ethanol through hydrogen-assisted C-C coupling over fluorine-modified copper

精准控制C1分子C-C偶联合成特定C2+化合物是C1化学中极具挑战性的难题。由于C2+化合物(如乙烯和乙醇)在化工和能源领域具有重要用途，将CO2直接转化为C2+产物极具吸引力。发展高效催化剂，实现高电流密度、高C2+选择性、高稳定性的“三高”性能，是推进电催化还原CO2走向实际应用的关键。研究团队针对电催化还原CO2中高CO2还原法拉第效率的催化剂常常活性低的问题，提出了适当提高催化剂活化水的能力对增加CO2还原活性的重要性，发展出氢助碳碳偶联(hydrogen-assisted C-C coupling)的新策略，在氟修饰的铜(F-Cu)催化剂上实现了CO2电催化还原制乙烯和乙醇的新突破。该研究工作实验部分主要由王野、张庆红教授指导，能源材料协同创新中心iChEM2016级博士生马文超、固体表面物理化学国家重点实验室高级工程师谢顺吉(共同第一作者)完成；理论计算部分由程俊教授指导，2017级硕士生刘彤彤(共同第一作者)、2016级博士生樊祺源完成。叶进裕博士为原位红外测试提供了支持。上海光源姜政研究员、孙凡飞博士、杨若欧为同步辐射表征提供了支持。 这是投稿的最终版本，正式出版的论文版本请访问官方链接（https://doi.org/10.1038/s41929-020-0450-0）。Electrocatalytic reduction of CO2 into multi-carbon (C2+) products is a highly attractive route for CO2 utilization. However, the yield of C2+ products remains low because of the limited C2+ selectivity at high CO2 conversion rate. Here, we report a fluorine-modified copper catalyst that exhibits an ultrahigh current density of 1.6 A cm−2 at C2+ (mainly ethylene and ethanol) Faradaic efficiency of 80% for electrocatalytic CO2 reduction in a flow cell. The C2-4 selectivity reaches 85.8% at a single-pass yield of 16.5%. We show a hydrogen-assisted C−C coupling mechanism between adsorbed formyl (CHO) intermediates for C2+ formation. Fluorine enhances water activation, CO adsorption and hydrogenation of adsorbed CO to CHO intermediate that can readily undergo coupling. Our findings offer an opportunity to design highly active and selective CO2 electroreduction catalysts with potential for practical applicationThis work was supported by the National Key Research and Development Program of the Ministry of Science and Technology of China (No. 2017YFB0602201), the National Natural Science Foundation of China (Nos. 21690082, 91545203, 21503176 and 21802110), We thank staffs at the BL14W1 beamline of the Shanghai Synchrotron Radiation Facilities (SSRF) for assistance with the EXAFS measurements.研究工作得到科技部重点研发计划（批准号：2017YFB0602201）和国家自然科学基金（批准号：21690082、91545203、21503176、21802110）项目的资助