The Climatic Fluctuation and Important Events of Holocene Megathermal in China

Data from various sources including the ice core, inland lakes , paleosols in loess and eolian sands, sea level fluctuations, paleozoological, archeological evidences especially palynology and bontanical studies of China are reviewed . Holocene Megathermal mainly appeared during 8. 5-3 ka BP and lasted for 5. 5 ka. There were several strong climatic fluctuations and cooling events during this period, e. g. it was an unstable temperature fluctuation phase during 8. 5-7. 2 ka BP and was accompanied with the increase of the precipitation as well as the northward and westward migration of the vegetation zone ; the rapid development of Neolithic Culture happened in this phase. It was a stable warm and wet phase from 7. 2 to 6 ka BP, i. e. Megathermal Maximum, when monsoon was rainfall almost throughout China, plants were unprecedentedly flourished, and the Yangshao Culture reached its climax. It is characterized by strong climatic fluctuation and adverse environment during 6-5 ka BP and the impact of strong     

THE RELATIONSHIP BETWEEN ENVIRONMENT CHANGE AND SE MONSOON STRENGTH, DAIHAI LAKE, INNER MONGOLIA

Daihai Lake, located in NW margin of SE monsoon region, belongs to the sensitive area for climatic fluctuation. The analysis of continuous sedimentary column with an age of 100 ka indicates that there exists the different quasiperiodicity in time scales for monsoon shift. The climatic fluctuation in the Daihai Basin shows all along the alternation of cold and dry with a warm and wet climatic pattern, suggesting that the strength and drift of SE monsoon play a controllable role in the climatic change.     

THE COMPARISON OF LANZHOU LOESS PROFILE WITH VOSTOK ICE CORE IN ANTARCTICA OVER THE LAST GLACIATION CYCLE

Loess near Lanzhou in the late Pleistocene is very sensitive to climatic fluctuations. The Beiyuan terrace profile in Linxia City, of which the curve of susceptibility tallies with the trend of isotopic curves of Vostok 2083 m ice core in Antarctica, is 35m thick. There are five layers of paleosols under Malan loess(L_1). Upper three layers (S_(1-a),S(1-b)and S_(1-c) correspond to three warm stages in last interglaciation, Interstadial of Last Glacial (C stage in Antarctic ice core)was clearly recorded in the Beiyuan profile, in which three layers of paleosols and two of loess were formed. The lowest section of the profile belongs to penultimate glaciation, in which fossils of cold-drought-resistant mammal and mollusc have been discovered.     

Synthesis of thiohydantoins under one-pot three-component solvent-free conditions

A direct and efficient one-pot three-component synthesis protocol was developed for the synthesis of thiohydantoins from readily and widely available substrates (isothiocyanates, ethyl chloroacetate, and amines) employing solvent-free conditions. Correspondence: Song Cao, Shanghai Key Laboratory of Chemical Biology, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China.     

PALEOMONSOONS OF CHINA OVER THE LAST 130,000 YEARS——PALEOMONSOON VARIATION

Based upon the effect of land-sea interaction on the paleomonsoon variation and the time series of climatic proxy-indicators, the historical Asian monsoon variation over the last 130,000 and 18,000 years has been reconstructed with an emphasis on the basic characteristics of summer monsoon circulation. The monsoon-climatic cycles and associated model of environmental development over the central and eastern China are proposed and the mechanism of paleomonsoon variation of China preliminarily discussed. The variation of East Asian monsoon circulation should be regarded as a regional result of both solar-radiation changes and the global glacial-interglacial cycles. The episodic uplifting of the Qinghai-Xizang Plateau since the late Miocene has to a large extent controlled the forming and evolution of the paleomonsoon circulation of China.     

《催化学报》庆祝何鸣元院士八十华诞专刊

《催化学报》以本期专刊的出版庆祝何鸣元院士八十华诞,表达对何先生五十多年来为我国催化及相关领域发展所作出的卓越贡献的崇高敬意!何鸣元先生1940年2月8日出生于上海,1961年毕业于华东纺织工学院(现东华大学)应用化学专业,同年进入石油化工科学研究院工作至今.1980-1984年作为访问学者赴美国西北大学化学系和美国得克萨斯大学奥斯汀分校化工系进行合作研究.2000年以来,应邀兼任华东师范大学教授,2003年领导建立上海市绿色化学与化工过程绿色化重点实验室.何鸣元先生担任过许多学术职务.曾任石油化工科学研究院总工程师、学术委员会副主任,中国科学院学部主席团成员、化学部副主任,中国化学会常务理事、绿色化学专业委员会主任,国际催化理事会理事,国际沸石分子筛协会副主席等.何鸣元先生长期从事催化材料、炼油化工催化剂与工艺研究.发明了一系列沸石分子筛合成新方法与炼油催化剂,开发了双反应区催化裂化增产汽油异构烷烃MIP工艺(Maximum Isoparaffin Process)等多个具有自主知识产权的新工艺,为发展我国重油裂化技术、提高催化裂化汽油辛烷值、开发新标准汽油生产技术等作出了突出贡献.何鸣元先生是我国绿色化学的奠基人之一,他以国民经济可持续增长为目标,大力倡导和推动绿色化学与化工学术研究与技术开发.2001年担任科技部国家基础研究重大项目(2001-2005)'石油炼制与基本有机化学品加工的绿色化学'首席科学家,推动了多项绿色炼油与化工新技术的突破和工业应用.针对碳资源利用过程中所面临的效率低、污染物排放严重等问题,2011年,何先生和合作者从碳资源加工、利用和循环等全周期考虑,提出了'绿色碳科学'的概念,对碳资源的高效、清洁、循环利用具有重要的指导作用.近年来,发起并主持了以'可持续发展能源化工的科学基础:绿色碳科学与绿色氢科学'沸石分子筛:等级特性、选择催化与分子工程'绿色生态环境与化学化工'等为主题的香山科学会议以及其它高水平学术会议,为相关学科指出了发展方向.何鸣元先生获得了许多学术奖励和荣誉.他于1995年当选为中国科学院院士,曾获得国家发明二等奖(1995)、何梁何利科学技术进步奖(2001)、中国催化成就奖(2012)、法国教育部棕榈叶骑士勋章(2012)、法国里昂高师荣誉博士学位(2016)、中国分子筛终身成就奖(2019)等,在国内外催化与石油化工界享有崇高的声誉.本期专刊收录了15篇学术论文,内容涉及新型分子筛催化剂的合成、单原子催化、光催化、电催化以及甲烷、二氧化碳、生物质等碳资源的催化转化等,一定程度上反映了何先生过去五十多年的研究兴趣,并展现了当前国际催化科学与技术研究的前沿和进展.在此,我们衷心感谢论文作者、审稿专家和《催化学报》编辑部等相关人员所给予的大力支持.     

An imidazolium tosylate salt as efficient and recyclable catalyst for acetylation in an ionic liquid

A novel non-metallic salt, 1-butyl-3-methylimidazolium tosylate ([bmim][OTs]) dissolved in the ambient temperature ionic liquid of 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF₄]), was found to be the efficient catalyst for acetylation with the advantages of good recyclability, avoidance of metal contamination, mild reaction conditions, and wide availability for substrates (alcohols, phenols, and amines), could completely replace organic bases, metal Lewis acids, or metallic triflates to fulfill acetylation by a nucleophilic catalytic mechanism, which was supported by ¹³C NMR analysis. Correspondence: Ye Liu, Shanghai Key Laboratory of Green Chemistry and Chemical Processes, Chemistry Department of East China Normal University, Shanghai 200062, China.     

Monthly sea surface temperature records reconstructed by δ~(18)O of reef-building coral in the east of Hainan Island, South China Sea

Stable oxygen isotopic compositions of a coral colony of Porites lutea obtained on acore allowed the reconstruction of a 56-a (1943-1998) proxy record of the sea surface tempera-tures. This coral δ~(18)O data are from the east of Hainan Island water (22°20＇N, 110°39＇E), SouthChina Sea. The relationship between δ~(18)O in the skeletal aragonite carbonate and the sea surfacetemperature (SST) is SST=-5.36 δ~(18)O_(PDB)-3.51 (r=0.73, n=470), dδ~(18)O/d(SST)=-0.187‰/℃; and the thermometer was set at monthly resolution. The 56-a (1943-1998) proxy record of thesea surface temperatures reflected the same change trend in the northern part of South China Seaas the air temperature change trend in China.     

SEDIMENTARY PROPERTIES AND ENVIRONMENTAL VARIATIONS FROM CONTINENTAL SLOPE TO DEEP SEA PLAIN IN THE NORTHERN SOUTH CHINA SEA SINCE LATE PLEISTOCENE

The South China Sea is the westernmost marginal sea in the west Pacific Ocean. On thebasis of the analyses of sedimentary components, biofossils, oxygen-carbon isotopes and theirdatings in four seafloor cores which were collected from the deep sea plain to continentalslope in the northern South China Sea, the environmental variations were basically similarto other tropical ocean areas, and their cycle changes in about the ages of 40 ka and 20 kawere more apparent since the late Pleistocene. During the warm climates, the depositionrate on the continental slope was about 2.6 times as rapid as on the deep sea plain margin.The seafloor in the deep sea plain was below the CaCO_3 compensation depth. During thecold periods, however, the deposition rate on the deep sea plain margin was slightly quickerthan on the continental slope due to the sea level reduction on a larger scale and moresupply of the terrigenous clastics.     

COMPARATIVE RESEARCH ON ENVIRONMENTAL EVOLUTION BETWEEN THE RECION OF ANTARCTIC GREAT WALL STATION AND CHINA

Through comparative analysis between the environmental changes in the region of KingGeorge Island in Antarctic and the characteristics of environmental evolution in the differentregions of China, the paper reveals the important similarity of the environmental evolutionbetween the two regions. The fine correspondence relations between the environmentalchanges of King George Island region in Antarctic, the glacial activities on the mountainousterrain in the western part of China, and the oscillation of the northern boundary of sub-tropical zone in the eastern part of China pointed out in this study serve as evidence to sup-port the interaction between the Northern and Southern Hemispheres. The uniformity of theclimatic changes of the King George Island region in Antarctic with the changes of sea levelof China and the world also supports the similarity of the trend of global changes in tem-perature since the Holocene. One must pay attention to the macroscopic and integrated studyof the whole earth in order     

Biomarkers in a peat deposit in Northern Spain (Huelga de Bayas,Asturias) as proxy for climate variation

Peatlands are peculiar ecosystems in which well-adapted communities grow and develop, recording the variation in climate and hydrological conditions inland. In addition necromass is well preserved and therefore peatlands can be used as palaeo-archives for environmental variation. In this work a peat core of depth 60 cm dated at the bottom of the peat deposit as ca. 250 cal AD from Huelga de Bayas (Asturias, Northern Spain) was studied to a resolution of 2–4 cm to investigate the evolution of the environmental conditions in the area. Samples were extracted with a dichloromethane/methanol ratio of 3:1 and studied by means of gas chromatography (GC) and mass spectrometry (GC–MS) in order to identify possible biomarkers of climatic variation during the period of peat formation. Lipid biomarker study allows the identification of periods in which Sphagnum or higher plants preferentially contributed to the peat profile. The absolute dating of the profile combined with the n-alkane record displayed five episodes of wetter conditions around ca. 250 cal AD (Roman Warm Period), 1080 and 1270 cal AD (Medieval Warm Period), 1460 cal AD (Little Ice Age) and 1920 cal AD (Recent warming), which are consistent with climate evolution in the region. Pentacyclic triterpenoids with hopane skeleton derived from microorganisms and with oleanane skeleton derived from higher plants were identified. The presence of their ketone and acetyl-derivatives, along with the presence of unstable hopane configurations indicates a low maturity of the peat profile. A tendency for the functionalised triterpenoids to decrease with depth was observed in the profile.     

Clean synthesis of azo compounds using Magtrieve™ in the ionic liquid [<Emphasis Type="Italic">bmim</Emphasis>][Br]

A series of azo compounds, N-aryl-2-phenyldiazenecarboxamides, and 4-substituted-1,2,4-triazoline-3,5-diones, were synthesized using Magtrieve™, a magnetically retrievable and recyclable oxidant, in the ionic liquid [bmim][Br] under neutral condition. This procedure has several advantages, such as greenness, mild reactions, simple manipulation, and reusability of reagent and solvent. Correspondence: Yanqing Peng, Shanghai Key Laboratory of Chemical Biology, Institute of Pesticides and Pharmaceuticals, East China University of Science and Technology, Shanghai 200237, China.     

PALEOMONSOONS OF CHINA OVER THE LAST 130,000 YEARS——PALEOMONSOON RECORDS

The characteristics of the modern monsoon climate o?China may be used as clues for recognizing the records of paleomonsoon climate. The present paper deals primarily with the various paleomonsoon records of the last 130,000 years in the southeast monsoon area. These records mainly come from the following three fields: (i) the historical, (ii) the geological, including loess-paleosol sequence, deserts, lakes, snowlines, timberlines, the phenomena of continental desertization and so on, and (iii) the biological, presented by vegetation and mammals. Among these records, the loess-paleosol sequence in the Loess Plateau reflects a climatic history characterized by alternation of two different climatic periods when the Asian winter monsoon and summer monsoon showed pronounced effects on environment, respectively.     

Chronology and origin of VMS deposits in Xinjiang, NW CHINA

VMS deposits in Xinjiang, NW China are widespread in the Altay, Tianshan and WestKunlun orogenic belt, mainly formed during the Proterozoic rifting and Phanerozoic post-orogenicextension and are related to the bimodal volcanism. The VMS deposits are middle and small inscale. According to assemblages of metallogenetic elements, they can be divided into four types(Cu-Zn, Cu-S, Pb-Zn-Cu and Pb-Zn types) with the Cu-Zn and Pb-Zn types being the most impor-tant ones. Research of isotopic chronology shows that the VMS deposits in Xinjiang were formedduring the Proterozoic, Ordovician, Deovonian, Carboniferous and Permian periods and usuallyunderwent multi-stage mineralization, especially the large-sized deposits usually have post-volcanic superimposed mineralization by tectonomagmatic or metamorphic hydrothermal metal-logenic fluids.     

Derivatives of benzothiadiazole-7-carboxylates: synthesis and biological activity

Salicylic acid (SA) and methyl jasmonate (MJ) are important plant signal molecules to cause systemic acquired resistance (SAR), while it’s reported that they also have wide spectrum antitumor activities. Benzothiadiazole-7-carboxylates are plant activators which can cause SAR just like SA and MJ. To investigate whether the benzothiadiazole-7-carboxylate family is endowed with anticancer activities, several benzothiadiazole-7-carboxylate derivatives are synthesized and their inhibition to P388 murine leukemia cell and A549 human lung cancer cell compared with MJ are evaluated. The data indicated that benzo-1,2,3-thiadiazole-7-carboxylic acid 2-benzoyloxyethyl ester has a higher inhibition ability to the cancer cell P388 and A549, compared with MJ. Correspondence: Yufang Xu, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, China.     

ON THE ABRUPT CHANGE IN SOUTH ASIAN SUMMER MONSOON CLIMATE AND ITS SYNCHRONISM WITH THE GLOBAL RAPID WARMING

This paper has analysed the major characteristics of long-term variation, of summermonsoon climate in South Asia since 1888. An abrupt enhancement of summer monsoon inthe 1920s and its synchronism with the global rapid warming have been detected by theMann-Kendall Rank Statistic test. Based on diagnostic analysis on the atmospheric circulationover the monsoon region and the thermal conditions of both ocean and land during theperiod of abrupt change, it is found that the warming over land was stronger and earlierthan that over the ocean, which would enhance the land-sea thermal contrast and thereforebe favorable to the development of monsoon low and the disturbance in the monsoon flow.This may be a direct factor for the abrupt enhancement of summer monsoon.     

The thickness of a liquid layer on the free surface of ice as obtained from computer simulation

Molecular dynamic simulations were performed for ice I(h) with a free surface by using four water models, SPC/E, TIP4P, TIP4P/Ice, and TIP4P/2005. The behavior of the basal plane, the primary prismatic plane, and of the secondary prismatic plane when exposed to vacuum was analyzed. We observe the formation of a thin liquid layer at the ice surface at temperatures below the melting point for all models and the three planes considered. For a given plane it was found that the thickness of a liquid layer was similar for different water models, when the comparison is made at the same undercooling with respect to the melting point of the model. The liquid layer thickness is found to increase with temperature. For a fixed temperature it was found that the thickness of the liquid layer decreases in the following order: the basal plane, the primary prismatic plane, and the secondary prismatic plane. For the TIP4P/Ice model, a model reproducing the experimental value of the melting temperature of ice, the first clear indication of the formation of a liquid layer, appears at about -100 degrees C for the basal plane, at about -80 degrees C for the primary prismatic plane, and at about -70 degrees C for the secondary prismatic plane.     

Monthly sea surface temperature records reconstructed by δ<Superscript>18</Superscript>O of reef-building coral in the east of Hainan Island,South China Sea

Stable oxygen isotopic compositions of a coral colony ofPorites lutea obtained on a core allowed the reconstruction of a 56-a (1943–1998) proxy record of the sea surface temperatures. This coral δ¹⁸O data are from the east of Hainan Island water (22°20’N, 110°39’E), South China Sea. The relationship between δ¹⁸O in the skeletal aragonite carbonate and the sea surface temperature (SST) is SST = -5.36 δ¹⁸O_PDB-3.51 (r = 0.73,n = 470), dδ¹⁸O/d(SST) = -0.187?/ °C; and the thermometer was set at monthly resolution. The 56-a (1943–1998) proxy record of the sea surface temperatures reflected the same change trend in the northern part of South China Sea as the air temperature change trend in China.     

Monthly sea surface temperature records reconstructed by δ18O of reef-building coral in the east of Hainan Island,South China Sea

Stable oxygen isotopic compositions of a coral colony ofPorites lutea obtained on a core allowed the reconstruction of a 56-a (1943–1998) proxy record of the sea surface temperatures. This coral δ¹⁸O data are from the east of Hainan Island water (22°20’N, 110°39’E), South China Sea. The relationship between δ¹⁸O in the skeletal aragonite carbonate and the sea surface temperature (SST) is SST = -5.36 δ¹⁸O_PDB-3.51 (r = 0.73,n = 470), dδ¹⁸O/d(SST) = -0.187‱/ °C; and the thermometer was set at monthly resolution. The 56-a (1943–1998) proxy record of the sea surface temperatures reflected the same change trend in the northern part of South China Sea as the air temperature change trend in China.

     

NORTHERN HEMISPHERIC SUMMER CLIMATIC JUMP IN THE 1960s (Ⅱ)——SEA LEVEL PRESSURE AND 500 hPa HEIGHT

The paper is to depict the major structures of the Northern Hemispheric summer sealevel pressure (SLP), 500 hPa height (H 500) and 500 hPa ridge-and-trough (RAT) field during1951-1980. The 1960s' jump was found in the major signal of each field as well as inthe series of many circulation parameters. The major part of the H 500 change was the heightlowering over the most of the Hemisphere during the 1960s, corresponding well to the sur-face temperature change. The SLP and RAT changed in a way similar to that of the rainfallchange, with regard to the southwest-to-northeast zonal structure in the geographical distri-butions of the major signals of all the three fields. The relationship between the changes ofsome circulation parameters and the regional rainfall is discussed.