mlsa-iai-msu-lab/ru_sci_bench_zho_cite_reranking huggingface dataset:
内蒙古准格尔煤田煤中镓的分布赋存与富集成因

采集了内蒙古准格尔煤田黑岱沟矿区6煤层剖面样品以及选煤厂的系列样品,并收集该煤田勘探期的大量钻孔资料,运用电离耦合等离子体发射光谱,X射线衍射,带能谱仪的扫描电子显微镜等方法,对煤中镓的分布,赋存,富集成因进行了研究.结果表明:(1)Ga在研究区煤中明显富集,各煤层中Ga的平均含量在18.8~26.0μg/g之间,但分布很不均匀,尽管Ga在黑岱沟煤矿主采煤层中富集成矿,但其他矿区煤中未达到成矿规模;(2)平面上,主采煤层中Ga在研究区北部以及中部富集;垂向上,太原组底部煤层(8,9)与山西组煤层(3,4)中Ga的含量较太原组中上部煤层(6上,6,6下)中高;同一煤层中,靠近顶底板的煤分层中Ga含量较中部分层中高;(3)煤中Ga主要存在于勃姆石与高岭石等矿物中.此外,腐殖酸对Ga有一定的吸附作用,从而造成风化煤中Ga含量较高;(4)物源区母岩性质,沉积环境,有机质,构造和岩浆热液等诸多地质因素控制着研究区煤中Ga的富集,其中物源区Ga含量水平起主导作用;(5)微量元素Ga迁移沉淀主要受控于主量元素Al,陆相与海侵相的环境都能产生铝土矿的沉淀,而海陆交互相的环境可能造成Ga与Al的分离.此外, Ga可能还以气相形式迁移,受地温影响,故高挥发分煤较低挥发分煤相对富集Ga
马来半岛和婆罗洲北部的化学风化作用:来自河流表层沉积物的黏土矿物和元素地球化学记录

硅酸盐岩的风化产物通常可以有效地用于研究陆地表面发生的化学风化作用及其控制因素.选择位于东南亚热带地区的马来半岛和婆罗洲北部,通过分析其主要流域表层沉积物的黏土矿物和主要元素地球化学组成,开展热带地区化学风化及其控制因素的现代过程研究.结果显示,马来半岛的黏土矿物组合以高岭石(平均80%)为主,其次为伊利石(17%),基本不含绿泥石和蒙脱石;而婆罗洲北部则是以伊利石和绿泥石为主,两者之和在西北和东北婆罗洲平均分别为84%和87%,其次为高岭石(14%),不含蒙脱石.通过全岩和黏土粒级颗粒主要元素地球化学分析发现,这两个地区的化学风化作用都呈现强烈状态.相对而言,从东北婆罗洲,西北婆罗洲到马来半岛,化学风化强度依次持续加强,马来半岛已达到非常强烈的化学风化状态.研究认为,以马来半岛和婆罗洲为代表的东南亚热带地区,热带温暖如一的气温和东亚季风降雨等气候条件是控制化学风化作用的一级因素,形成遍布热带地区的强烈化学风化作用;构造活动和母岩性质是影响化学风化作用的次级因素,但仍然对风化产物的产生重要影响,形成马来半岛和婆罗洲完全不同的黏土矿物组合
TRIM-9 functions in the UNC-6/UNC-40 pathway to regulate ventral guidance

TRIpartite Motif (TRIM) family proteins are ring finger domain-containing, multi-domain proteins implicated in many biological processes. Members of the TRIM-9/C-I subfamily of TRIM proteins, including TRIM-9, MIDI and MID2, have neuronal functions and are associated with neurological diseases. To explore whether the functions of C-I TRIM proteins are conserved in invertebrates, we analyzed Caenorhabditis elegans and Drosophila trim-9 mutants. C. elegans trim-9 mutants exhibit defects in the ventral guidance of hermaphrodite specific neuron (HSN) and the touch neuron AVM. Further genetic analyses indicate that TRIM-9 participates in the UNC-6-UNC-40 attraction pathway. Asymmetric distribution of UNC-40 during HSN development is normal in trim-9 mutants. However, the asymmetric localization of MIG-10, a downstream effector of UNC-40, is abolished in trim-9 mutants. These results suggest that TRIM-9 functions upstream of MIG-10 in the UNC-40 pathway. Moreover, we showed that TRIM-9 exhibits E3 ubiquitin ligase activity in vitro and this activity is important for TRIM-9 function in vivo. Additionally, we found that Drosophila trim-9 is required for the midline attraction of a group of sensory neuron axons. Over-expression of the Netrin/UNC-6 receptor Frazzled suppresses the guidance defects in trim-9 mutants. Our study reveals an evolutionarily conserved function of TRIM-9 in the UNC-40/Frazzled-mediated UNC-6/Netrin attraction pathway
优质高产春小麦新品种--沈麦112

沈麦112系沈阳农业大学农学院通过有性杂交多年选育的一个优质,高产春小麦新品种,2009年12月经辽宁省农作物品种审定委员会审定,审定编号为辽审麦[2009]34号
抗条锈丰产冬小麦新品种--中梁30号

中梁30号(原系谱号9996-8-1)是天水市农业科学研究所用生产上具有持久抗条锈性的小麦品种holdfast为母本,抗病高产品种中梁22号为父本经系谱法选育而成的冬小麦新品种.该品种2010年通过甘肃省品种审定委员会审定
Natural history of heartburn: A 10-year population-based study

AIM: To study the natural history and prevalence of heartburn at a 10-year interval, and to study the effect of heartburn on various symptoms and activities. METHODS: A population-based postal study was carried out. Questionnaires were mailed to the same ageand gender-stratified random sample of the Icelandic population(aged 18-75 years)in 1996 and again in 2006. Subjects were classified with heartburn if they reported heartburn in the preceding year and/or week, based on the definition of heartburn. RESULTS: Heartburn in the preceding year was reported in 42.8%(1996)and 44.2%(2006)of subjects, with a strong relationship between those who experienced heartburn in both years. Heartburn in the preceding week was diagnosed in 20.8%. There was a significant relationship between heartburn, dyspepsia and irritable bowel syndrome. Individuals with a body mass index(BMI) below or higher than normal weight were more likely to have heartburn. Heartburn caused by food or beverages was reported very often by 20.0%of subjects. CONCLUSION: Heartburn is a common and chronic condition. Subjects with a BMI below or higher than normal weight are more likely to experience heartburn. Heartburn has a great impact on daily activities, sleep and quality of life
Percutaneous aspiration and drainage with adjuvant medical therapy for treatment of hepatic hydatid cysts

AIM: To determine the efficacy and success of percutaneous aspiration irrigation and reaspiration(PAIR)in the management of hepatic hydatidosis. METHODS: Twenty-six patients with 32 hepatic hydatid cysts had PAIR. Twenty-two patients received at least 2 wk of drug therapy before the procedure was carried out to reduce the risk of recurrence from spillage during the procedure. The procedure was performed under local anesthesia with a 19-gauge 20 cm long needle, the cyst was punctured, cystic content(approximately 30 mL)was aspirated by a 12-14 F pigtail catheter and aspirated fluids were sent for analysis. Once the cyst was almost empty, two-thirds of the net amount of material aspirated was replaced by hypertonic saline and left in the cavity for about 30 min, with the catheter left in place for reaspiration of most of the fluid. When the amount of fluid drained was less than 10 mL per 24 h, the drainage catheter was removed. RESULTS: All 32 cysts showed evidence of immediate collapse after completion of the procedure, and before discharge from hospital, ultrasound examination showed fluid reaccumulation in all cysts. Serial follow-up showed a progressive decrease in the size and change in the appearance of cysts. To confirm the sterility of these cystic cavities, seven cysts were reaspirated on average 3 mo after the procedure. Investigations revealed no viable scolices. CONCLUSION: PAIR using hypertonic saline is very effective and safe with proper precautions
Bones and Crohn's: No benefit of adding sodium fluoride or ibandronate to calcium and vitamin D

AIM: To compare the effect of calcium and cholecalciferol alone and along with additional sodium fluoride or ibandronate on bone mineral density (IBMD) and fractures in patients with Crohn's disease (CD). METHODS: Patients (n =148) with reduced BMD (T-score< -1) were randomized to receive cholecalciferol (1000 IU) and calcium citrate (800 mg) daily alone(group A, n = 32) or along with additional sodium fluoride (25 mg bid) (group B, n = 62) or additional ibandronate (1 mg iv/3monthly) (group C, n = 54). Dual energy X-ray absorptiometry of the lumbar spine (L1-L4) and proximal right femur and X-rays of the spine were performed at baseline and after 1.0, 2.25 and 3.5 years. Fracture-assessment included visual reading of X-rays and quantitative morphometry of vertebral bodies (T4-L4). RESULTS: One hundred and twenty three (83.1%) patients completed the first year for intention-to-treat (ITT) analysis. Ninety two (62.2%) patients completed the second year and 71 (47.8%) the third year available for per-protocol (PP) analysis. With a significant increase in T-score of the lumbar spine by +0.28 ± 0.35 [95% confidence interval (CI): 0.162-0.460, P < 0.01], +0.33 ± 0.49 (95% CI: 0.109-0.558, P < 0.01), +0.43 ± 0.47 (95% CI: 0.147-0.708, P < 0.01) in group A, +0.22 ± 0.33 (95% CI: 0.125-0.321, P < 0.01); +0.47 ± 0.60 (95% CI: 0.262-0.676, P < 0.01), +0.51 ± 0.44 (95% CI: 0.338-0.682, P < 0.01) in group B and +0.22 ± 0.38 (95% CI: 0.111-0.329, P < 0.01), +0.36 ± 0.53 (95% CI: 0.147-0.578, P < 0.01), +0.41 ± 0.48 (95% CI: 0.238-0.576, P < 0.01) in group C, respectively, during the 1.0, 2.25 and 3.5 year periods (PP analysis), no treatment regimen was superior in any in- or betweengroup analyses. In the ITT analysis, similar results in all in- and between-group analyses with a significant ingroup but non-significant between-group increase in T-score of the lumbar spine by 0.38 ± 0.46 (group A, P < 0.01), 0.37 ± 0.50 (group B, P < 0.01) and 0.35 ± 0.49 (group C, P < 0.01) was observed. Follow-up in ITT analysis was still 2.65 years. One vertebral fracture in the sodium fluoride group was detected. Study medication was safe and well tolerated. CONCLUSION: Additional sodium fluoride or ibandronate had no benefit over calcium and cholecalciferol alone in managing reduced BMD in CD
Systematic review on the surgical treatment for T1 gallbladder cancer

AIM: To evaluate the efficacy of simple and extended cholecystectomy for mucosa (Tla) or muscularis (Tlb) gallbladder (GB) cancer. METHODS: Original studies on simple and extended cholecystec:omy for Tla or Tlb GB cancer were searched from MEDLINE (PubMed), Cochrane Library, EMBase, and Cancer Lit using the search terms of GB, cancer/carcinoma/tumor/neoplasm. RESULTS: Twenty-nine out of the 2312 potentially relevant publications met the eligibility criteria. Of the 1266 patients with GB cancer included in the publications, 706 (55.8%) and 560 (44.2%) had Tla and Tlb GB cancer, respectively. Simple cholecystectomy for Tla and Tlb GB cancer was performed in 590 (83.6%) and 375 (67.0%) patients, respectively (P < 0.01). In most series, the treatment of choice was simple cholecystectomy for Tla GB cancer patients with a 5-year survival rate of 100%,. Lymph node metastasis was detected in 10.9% of the Tlb GB cancer patients and in 1.8% of the Tla GB cancer patients, respectively (P < 0.01). Eight patients (1.1%) with Tla GB cancer and 52 patients (9.3%) with Tlb GB cancer died of recurrent GB cancer (P < 0.01). CONCLUSION: Simple cholecystectomy represents the adequate treatment of Tla GB cancer. There is no definite evidence that extended cholecystectomy is advantageous over simple cholecystectomy for Tlb GB cancer
5例神经梅毒临床分析

神经梅毒的临床表现 梅毒(syphilis)是由梅毒螺旋体(Treponema pallidun, TP)引起的一种慢性传染病,主要通过性接触和血液传播.TP几乎可以侵犯人体所有器官,因此梅毒的临床表现极为复杂,并可通过胎盘传播引起流产,早产,死产和胎传梅毒,危害性极大.根据梅毒感染的途径可分为获得性(后天)梅毒和胎传(先天)梅毒,其中获得性梅毒更为常见,临床分期可分为一期,二期和三期梅毒.一期梅毒主要表现为硬下疳和硬化性淋巴结炎,一般无全身症状.一期梅毒未经治疗或治疗不彻底,TP由淋巴系统进入血液循环,形成菌血症播散全身,引起皮肤黏膜及系统性损害,为二期梅毒.二期梅毒可出现神经系统损害,主要以脑膜,脊髓血管梅毒为主,二期梅毒如治疗不当,大约40%患者可发生三期梅毒,出现梅毒性树胶肿,梅毒骨,心血管梅毒和实质性神经梅毒.三期梅毒神经系统损害主要表现为脊髓痨和麻痹性痴呆.神经梅毒发生率为10%,多在感染后3~20年后发生,但也有报道认为梅毒感染后早期即可出现神经系统梅毒
西江引水工程大直径钢管泥水平衡顶管施工技术

广州西江引水工程部分标段顶管工程顶进的钢管直径大(DN2 800),穿越地层主要为中砂层,具有一定的施工难度,选用合适的顶管机头,采取泥水平衡顶管施工技术,确保了施工的顺利进行?详细介绍了施工中顶管出洞?正常顶进和顶入接收井等阶段需要特别注意的问题
自动喷水灭火系统设计中枝状和格栅状管网的经济性比较

现代建筑中,大型厂房及物流仓库越来越多?相关的消防工程设计:传统的枝状系统不但耗费材料又增加了施工成本,而且管网的流量?压力都很不均匀;环状格栅管网中的压力和流量均匀性好且泵所需的扬程?流量和功率较小?利用专业的消防工程CAD计算软件,比较消防给水系统多方案设计优劣性,以期寻求在满足相关规范的前提下,降低物资耗用量及工程投资额,以达到最优化的设计方案
太阳能热水系统冷水计算温度取值的讨论

通过对冷水温度实测数据的规律性研究,对其设计取值合理性对太阳能热水系统经济性和设计准确性影响的分析,提出了太阳能热水系统冷水计算温度取值原则?针对目前我国冷水温度实测数据设计不易获取情况,基于对环境温度与冷水温度之间关联规律的分析,提出了冷水计算温度简化取值方法,并对该取值适用范围进行了限定
涉外星级厦门威斯汀酒店自动喷水灭火系统设计

针对超高层涉外星级酒店建筑及外方经营管理的特点,介绍厦门威斯汀酒店自动喷水灭火系统的设计情况及体会,并对相关问题进行探讨,供设计参考
厌氧滤池--MBR工艺处理小规模乳制品废水

采用厌氧滤池--MBR工艺处理某公司乳制品废水?工程实践表明,该工艺具有稳定的处理效果?自2008年10月投入运行以来,出水水质良好,出水CODCr<50 mg/L,BOD5<30 mg/L,SS<70 mg/L,达到<<辽宁省污水与废气排放标准>>(DB 21--60--89)一级标准?运行费用为0.45元/m3
城市污水处理厂磷的形态变化规律研究

对以A-A2/O--微絮凝--砂滤为处理工艺的某污水处理厂全流程磷的形态变化进行现场研究?结果表明,各处理构筑物中的磷主要以正磷酸盐形式存在,且正磷酸盐浓度在整个处理流程中的变化规律为:从沉砂池到前置反硝化池减小,从前置反硝化池到厌氧池增大,从厌氧池到好氧池减小,在厌氧池达到最大,在砂滤池出水达到最小?而正磷酸盐占总磷比例在二沉池出水处最大,由此判定二沉池出水处为最佳投药点?聚磷酸盐和有机磷浓度占总磷的比例沿处理流程呈先减小后增大的趋势
复合二氧化氯在饮用水处理应用中的水质安全问题

依据ClO2副产物ClO2-和ClO3-的毒性及其两者间关系,对满足<<复合二氧化氯发生器>>(GB/T20621--2006)要求的发生器的ClO2转化率?ClO2/Cl2值指标进行分析,指出其产出物中氯气(Cl2)含量超过50%(质量分数),对于控制THMs意义不大?未经反应的NaClO3原料残余量达到有效氯投加量的20%~30%,会对饮用水造成潜在严重污染,毒理指标ClO3-含量极易超标?只有在饮用水处理中应用具备残液分离及回收技术的发生器才可保证水质安全?最后对目前众多中小水厂选用复合二氧化氯的误区进行了初探
薏苡仁辅助治疗肺癌

薏苡仁,甘、淡,微寒,可清热排脓. 肺癌有咳黄痰带血丝,低烧之症,颇似内痈之症. 笔者以千金苇茎汤加减,重用薏苡仁辅助治疗肺癌,常能使癌肿得到控制,生活质量提高. 例举病案如下
集成LiDAR和遥感影像生成高质量真正射影像研究

随着社会经济发展,社会各界对城市大比例尺正射影像的需求日益增长.传统正射影像生成仅利用DEM对地形投影变形进行纠正,沿用此方法生成大比例尺正射影像无法纠正建筑物,树木等目标的投影变形,在城市地区将存在大量遮挡和偏移变形等错误空间信息.此时,需要利用包含地表及地表附着物的DSM对遥感影像进行正射纠正,称为"真正射影像生成"
草豆蔻中山姜素和小豆蔻明的HPLC测定及提取工艺优化

目的:建立起高灵敏度的草豆蔻中山姜素和小豆蔻明的HPLC测定方法和最佳提取工艺. 方法:利用高效液相色谱测定山姜素和小豆蔻明含量, 采用L_(16)(4~5)正交试验设计法, 考察乙醇浓度、提取次数、提取温度、提取时间和溶剂用量对二者提取的影响, 并对其稳定性进行探讨. 结果:色谱柱Agilent Eclipse XDB-C_(18)(4.6 mm×150 mm, 5μm), 流动相梯度:0~16 min, 甲醇-1%乙酸=52:48;16~36 min, 甲醇-1%乙酸=62:38. 检测波长梯度:0~16 min, 286 nm;16~36 min, 346 nm. 最佳提取工艺为20倍量的100%乙醇回流, 每次2 h, 提取3次. 结论:测定方法灵敏、可靠, 提取工艺稳定, 为草豆蔻的药物综合利用提供了依据
听力障碍儿童视觉注意能力及行为问题

儿童听力障碍与言语发育缺陷的关系已被人们所熟知,改善听力促进言语发育成为研究的热点.然而,言语只是多元认知的一个方面,对听力障碍儿童的非言语认知能力如注意能力,行为问题却缺乏系统研究.本文探讨了听力障碍儿童视觉注意发展及行为的特征,将有助于对听力障碍儿童早期采取针对性的干预措施
Theoretical Treatment of Target Coverage in Wireless Sensor Networks

The target coverage is an important yet challenging problem in wireless sensor networks, especially when both coverage and energy constraints should be taken into account. Due to its nonlinear nature, previous studies of this problem have mainly focused on heuristic algorithms; the theoretical bound remains unknown. Moreover, the most popular method used in the previous literature, i.e., discretization of continuous time, has yet to be justified. This paper fills in these gaps with two theoretical results. The first one is a formal justification for the method. We use a simple example to illustrate the procedure of transforming a solution in time domain into a corresponding solution in the pattern domain with the same network lifetime and obtain two key observations. After that, we formally prove these two observations and use them as the basis to justify the method. The second result is an algorithm that can guarantee the network lifetime to be at least (1 - e) of the optimal network lifetime, where c can be made arbitrarily small depending on the required precision. The algorithm is based on the column generation (CG) theory, which decomposes the original problem into two sub-problems and iteratively solves them in a way that approaches the optimal solution. Moreover, we developed several constructive approaches to further optimize the algorithm. Numerical results verify the efficiency of our CG-based algorithm
寻觅科学开拓的新方向

美国哥伦比亚大学著名的物理学教授Brian Greene曾这样理解科学突破:大家都从这个方向看问题,而你却从后面看过去.因为不同的思路往往可以发现全新的东西,而如果我们受控于我们所看到的东西,那么就会被引导到同一个方向.从科学观点来看,转换视角非常重要
平淡蕴学识,润物细无声

王振义院士一生中拿过无数奖,其中最有份量的,除开美国"凯特林医学奖",瑞士布鲁巴赫肿瘤研究奖,法国台尔杜加科学奖外,国内就是中国国家最高科学技术奖了.国家最高科学技术奖可谓是中国的诺贝尔奖.业内称,王振义院士是中国唯一一个拿过除了诺贝尔医学奖以外所有国际医学大奖的科学家.就是这样一个学术界的得奖大家,王振义始终自认为他仅仅是一位医生,一位教师.对他来讲,只要病人,准确地说是白血病人,信赖他的医术;学生欣赏他的为师之道就够了,至于名利他看得很淡,在他看来,一项高级别国际奖项的获得还不及一个白血病患者的死而复生给他带来的喜悦,一个辉煌称号的授予不及学生们的光彩夺目给他带来的享受.每次隆重的登台领奖之后,王老的习惯是一如既往恢复平静的作息,工作
小潮气量联合低PEEP通气在肝移植手术肺损伤保护中的应用

肝病晚期保守治疗效果差,肝移植手术是治疗晚期肝病的最有效手段.许多肝病晚期患者术前并发不同程度的肺部疾病,术中特别是无肝期和新肝期容易出现急性肺水肿和肺损伤等肺部相关并发症.近年来我科在肝移植手术中采用小潮气量,低呼气末正压(positive and expiratory pressure, PEEP)通气来预防肺部并发症,取得了满意的效果,现报告如下
第二届亚洲功能材料与结构力学大会简介

第二届亚洲功能材料与结构力学大会于2010年10月22~25日在南京航空航天大学成功举行, 本届大会由中国力学学会和江苏省力学学会主办、南京航空航天大学承办.会议延续在日本Matsue召开首届大会的目的: 旨为亚洲及其周边地区从事功能材料与结构力学的科研工作者提供一个交流的平台, 共同促进该领域在理论与应用方面的发展
On new chaotic mappings in symbol space

A well known chaotic mapping in symbol space is a shift mapping. However, other chaotic mappings in symbol space exist too. The basic change is to consider the process not only at a set of times which are equally spaced, say at unit time apart (a shift mapping), but at a set of times which are not equally spaced, say if the unit time can not be fixed. The increasing mapping as a generalization of the shift mapping and the k-switch mapping are introduced. The increasing and k-switch mappings are chaotic
A discrete model of a rope with bending stiffness or Viscous damping

A discrete model of a rope is developed and used to simulate the plane motion of the rope fixed at one end. Actually, two systems are presented, whose members are rigid but non-ideal joints involve elasticity or dissipation. The dissipation is reflected simply by viscous damping model, whereas the bending stiffness conception is based on the classical curvature-bending moment relationship for beams and simple geometrical formulas. Equations of motion are derived and their complexity is discussed from the computational point of view. Since modified extended backward differentiation formulas (MEBDF) of Cash are implemented to solve the resulting initial value problems, the technique scheme is outlined. Numerical experiments are performed and influences of the elasticity and damping on behaviour of the model are analyzed. Basic energy principles are used to verify the obtained results
Dynamic analysis of an offshore pipe laying operation using the reel method

A system designed for a rigid and flexible pipe laying purposes is presented in the paper. Mathematical and numerical models are developed by using the rigid finite element method (RFEM). The RFEM is an efficient solution in the time domain. Static and dynamic problems related to pipe installation are solved by taking the advantage of simple interpretation and implementation of the method. Large deformations of the pipe during spooling and when it is reeled out at sea are considered. A material model implemented is used to take into consideration nonlinear material properties. In particular, the full elasto-plastic material characteristics with hardening and Bauschinger effect are included. Dynamic analyses are performed and the results attached in this work demonstrates how the sea conditions influence the machinery and pipeline, assuming a passive reel drive system. The influence of several other operational parameters on dynamic loads is verified. An active system, implemented as a part of the mathematical model, improves the system performance. Some results are presented as well
SOLUBLE POLYIMIDES FROM A SEMI-ALIPHATIC DIAMINE CONTAINING ESTER, AMIDE AND ETHER GROUPS

A diamine was synthesized by two successive reactions. Nucleophilic reaction of 4-hydroxybenzoic acid with terephthaloyl chloride yielded terephthaloyl bis(4-oxybenzoic) acid. Then reaction of this compound with 1,8-diamino-3,6-dioxaoctane via Yamazaki method resulted in preparation of diamine named terephthalic acid bis(4-{2-[2-(2-amino ethoxy)ethoxy]ethyl carbamoyl}phenyl) ester. After fully characterization it was used to prepare new polyimides through polycondensation with different dianhydrides using trimethylchlorosilane. Characterization of polymers was achieved by common methods and their physical properties including inherent viscosity, thermal behavior, thermal stability, crystallinity and solubility were studied. Prepared polyimides showed improved solubility and good thermal stability
On the Evolution and Structure of a Radiation Fog Event in Nanjing

An extremely dense radiation fog event during 10-11 December 2007 was studied to understand its macro-/micro-physics in relation to dynamic and thermodynamic structures of the boundary layer, as well as its structural evolution in conjunction with the air-surface exchange of heat and water vapor. The findings are as follows. The extreme radiation fog process was divisible into formation, development, mature, and dissipation phases, depending on microstructure and visibility. This fog event was marked by rapid evolution that occurred after sunrise, when enhanced surface evaporation and cold air intrusion led to a three order of magnitude increase in liquid water content (LWC) in just 20 minutes. The maximum droplet diameter (MDD) increased four-fold during the same period. The fog structure was two-layered, with the top of both the surface-layer and upper-layer components characterized by strong temperature and humidity inversions, and low-level jets existed in the boundary layer above each fog layer. Turbulence intensity, turbulent kinetic energy, and friction velocity differed remarkably from phase to phase: these features increased gradually before the fog formation and decreased during the development phase; during the mature and dissipation phases these characteristics increased and then decreased again. In the development and mature stages, the mean kinetic energy of the lower-level winds decreased pronouncedly, both in the horizontal and vertical directions
Changes in the East Asian Cold Season since 2000

Using NCEP-NCAR reanalysis data and observational data from meteorological stations in China, the evolution of the East Asian cold season (EACS) and its long-term changes after 2000 were studied. A monsoon tendency index (MTI), defined as the temporal difference of the East Asian monsoon index, indicates that the winter monsoon setup has been postponed in autumn, while the setup has quickened in early winter. In mid winter, the EACS breakdown process has accelerated, while it has lingered in late winter. The authors suggest that the postponement of monsoon setup in autumn may be caused by strong global warming at the lower levels, which further limits the setup time period and leads to the quickening of the setup process in early winter. Meanwhile, a north-south seesaw of temperature tendency change in China can be observed in December and February, which may be related to large-scale circulation changes in the stratosphere, characterized by a polar warming in mid winter and polar cooling in early spring. This linkage is possibly caused by the dynamical coupling between stratosphere and troposphere,'via the variation of planetary wave activities. In spring, the speed of the EACS breakdown has decreased, which favors the revival of the EACS in East Asia
Long-Term Trends in Extreme Temperatures in Hong Kong and Southern China

The observed long-term trends in extreme temperatures in Hong Kong were studied based on the meteorological data recorded at the Hong Kong Observatory Headquarters from 1885-2008. Results show that, over the past 124 years, the extreme daily minimum and maximum temperatures, as well as the length of the warm spell in Hong Kong, exhibit statistically significant long-term rising trends, while the length of the cold spell shows a statistically significant decreasing trend. The time-dependent return period analysis also indicated that the return period for daily minimum temperature at 4°C or lower lengthened considerably from 6 years in 1900 to over 150 years in 2000, while the return periods for daily maximum temperature reaching 35°C or above shortened drastically from 32 years in 1900 to 4.5 years in 2000. Past trends in extreme temperatures from selected weather stations in southern China from 1951-2004 were also assessed. Over 70% of the stations studied yielded a statistically significant rising trend in extreme daily minimum temperature, while the trend for extreme maximum temperatures was found to vary, with no significant trend established for the majority of stations
Application of ATOVS Radiance-Bias Correction to Typhoon Track Prediction with Ensemble Kalman Filter Data Assimilation

In this paper, firstly, the bias between observed radiances from the Advanced TIROS-N Operational Vertical Sounder (ATOVS) and those simulated from a model first-guess are corrected. After bias correction, the observed minus calculated (O-B) radiances of most channels were reduced closer to zero, with peak values in each channel shifted towards zero, and the distribution of O-B closer to a Gaussian distribution than without bias correction. Secondly, ATOVS radiance data with and without bias correction are assimilated directly with an Ensemble Kalman Filter (EnKF) data assimilation system, which are then adopted as the initial fields in the forecast model T106L19 to simulate Typhoon Prapiroon (2006) during the period 2-4 August 2006. The prediction results show that the assimilation of ATOVS radiance data with bias correction has a significant and positive impact upon the prediction of the typhoon's track and intensity, although the results are not perfect