Chemical indexes of Paleoproterozoic sedimentary rocks from Liaohe Group,North China Craton:Implications for paleoclimate and provenance

Paleoproterozoic supracrustal materials have been widely identified in North China Craton,such as the Liaohe-,Hutuo-and Lyuliang groups.The Liaohe Group in the eastern part of the North China Craton is dominated by deformed and metamorphosed sedimentary and volcanic successions.Compared with that of the coeval volcanic rocks,geochemistry of the sedimentary rocks from the Liaohe Group has rarely been studied in detail,which can possibly provide information on the paleoclimate and provenance.The authors analyzed the whole-rock and detrital zircon geochemistry of sedimentary rocks from the Liaohe Group against a uniform process and proposed their different ways of paleoweathering of the lower and upper formations.That is to say,although the lower and upper formations within the Liaohe Group might be derived from the similar source composition in a tectonically active setting,the paleoclimate that they experienced was not exactly the same.The predominant derivations are the Paleoproterozoic granitoids and basalts within the Liaohe Group,with minor input of Archean continental crust.This study highlights the contributions of the Paleoproterozoic mafic sources,which has been generally overlooked in the previous researches.

Geochemical characteristics and environmental implications of loess sequences in the Loess Plateau

The major,trace,and rare earth elements of the Duanjiapo(DJP)section in the south of the Loess Plateau,the Jiaxian(JX)section in the north,and the Jiuzhoutai(JZT)section in the west are studied.The results show that the main elemental characteristics of loess in three profiles are consistent with the upper continental crust(UCC).In terms of trace elements,Th,Nb,Zr,Hf,Y,Cs,W,Cr,V,Li,and Pb show relative enrichment compared with UCC;Rb,Ba,Sr and Be exhibit relative depletion.The average ofΣREE is 171.91ppm with a negative anomaly forδEu and essentially no anomaly forδCe.The results of K_(2)O/Na_(2)O,Rb/Sr ratios,as well as the leaching co-efficient from three profiles,indicate DJP>JX>JZT,suggesting that DJP experiences the strongest weathering leaching effect.The chemical index of alteration(CIA)reveals that all three profiles of loess are in the primary stage of Ca and Na depletion.DJP is generally in the early to moderate stage of chemical weathering,while JX and JZT are both in the early stage.

GIS-Based Assessment of Soil Chemical and Physical Properties as a Basis for Land Reclamation in Toshka Area, Aswan, EGYPT

The accurate assessment of soil properties is a crucial factor for composing and implementing reclamation plans. The main objective of this study was to evaluate soil chemical and physical properties and calculate the chemical and fertility index for assisting land reclamation in Toshka area. The Toshka area is located between latitudes 31°32'N and 31°36'N and longitudes 32°40'E and 32°60'E. GIS was used to select 16 sites. The results revealed the soil has undesirable characteristics. The soil pH ranged from slightly alkaline to moderately alkaline. Furthermore, it was characterized as saline (with a ECe of 4.65 - 11.45 dS⋅m−1) and moderately calcareous soil (with CaCO3 at 11.85% - 17.20%). The soil had a low soil organic matter content which did not exceed 0.18%. The soil was dominated by a sandy loam texture (62.50%) followed by a sandy clay loam texture (18.75%). The bulk density, total soil porosity and saturated hydraulic conductivity values varied with 1.38 - 1.55 Mg⋅cm−3, 41.85% - 48.45% and 1.20 - 3.34 cm⋅h−1, respectively. The chemical index ranged from low to moderate quality. The correlations between the parameters osculated between negative and positive. Therefore, the soil may be reclaimed if the soil properties are improved and crop selection is optimized for this soil.

Darcy's Law Expressed by Chemical Index

The Darcy's formula expressed by chemical indexes (ion activity a and saturation index β) is derived with the aid of the kinetics of multi-mineral dissolution. The implication of the formula and the relationship between the formula and the original Darcy's law expressed by hydraulic index (hydraulic gradient, Ⅰ) are discussed here. An analytic expression is established in this paper for the determination of the residence time of groundwater by chemical indexes, whose equivalence to isotopic age is studied. The formulas are derived from the calculation of permeability coefficient (K), conductivity coefficient (T) and actual velocity of groundwater (U). Finally, this paper introduces hydrogeological chemical kinetics constant (k j) and its determination method, differential and integral equations for chemical kinetics of groundwater in three-dimensional space.

Analysis of Physical and Chemical Indices and Quality of Blueberry Wines from Gardenblue and Baldwin

Gardenblue and baldwin rabbiteye blueberry are the alien varieties. The physical and chemical indices of the fresh fruits of the two varieties were analyzed. The results showed that the sugar-acid ratio was higher in gardenblue than in baldwin, and the content of anthocyanins was also higher in gardenblue than in baldwin, so the quality of gardenblue was better. The gardenblue wine has better quality than the baldwin wine, and the two kinds of wines both have good quality. Therefore, gardenblue and baldwin both are suitable for the brewing red wine as the raw material.

Effects of Different Processing Modes of Reconstituted Tobacco on Cigarette Quality

In order to explore the most suitable mode for the primary processing model of reconstituted tobacco, another two kinds of conditioning process schemes for reconstituted tobacco were designed based on the existing reconstituted tobacco processing method. Comparative analysis and evaluation were conducted for moisture content uniformity, intrinsic chemical compositions, casing uniformity, blending uniformity and sensory quality of the samples from the three kind of processing modes. The results showed that loosing and conditioning or the vacuum conditioning pretreatment of the reconstituted tobacco could effectively reduce the difference in moisture content during the blending, and improve the casing uniformity and blending uniformity. Moreover, the samples with the loosing and conditioning pretreatment had higher total sugar and reducing sugar contents, which indicated that the loosing and conditioning pretreatment method was more favorable for the improvement of the intrinsic quality of cigarettes. In addition, the three kinds of aromatic components contents of cigarettes using the loosing and conditioning pretreatment were higher,and the casing uniformity, blending uniformity and overall sensory quality of this pretreatment were all superior to that of the other two kinds of reconstituted tobacco pretreatment methods. The contents of total sugar, reducing sugar as well as the three kinds of aromatic components of cigarettes processed with vacuum conditioning pretreatment were all slightly lower than those of the existing methods, but the casing uniformity and blending uniformity were improved, while it showed small difference in the sensory quality with the existing processing method.

Effect of Dehulling and Hydrothermal Treatment on the Amino Acid Content of Soriz (<i>Sorghum oryzoidum</i>)

Cereals are the basic element in ensuring the food security of the population through the significant intake of carbohydrates, proteins, dietary fiber, vitamins and minerals. The processing of cereals leads to changes in their nutritional quality, which could lead to both reduced nutrients and anti-nutrients. Gluten-free cereal varieties attract attention as raw materials to improve the nutritional quality of food and to diversify the product range. Sorghum (Sorghum oryzoidum) is a hybrid of sorghum, obtained at the Institute for Scientific Research for Corn and Sorghum in the Republic of Moldova, by crossing Sudan grass (S. sudanense) and bicolor sorghum (S. bicolor). The research aimed to determine the impact of dehulling and hydrothermal treatment on the amino acid content of soriz. The obtained results reported that the dehulling and hydrothermal treatment led to the uneven modification of the amino acid content in the investigated samples. As a result of dehulling, the total amount of essential amino acids decreased by 19.8% compared to the native grain. Boiling whole grains without prior hydration led to 34% loss of essential amino acids compared to native grains, and pre-hydration of the grains and subsequent boiling reduced essential amino acid losses by 8% compared to cooked grains without hydration. Boiling grains with pre-hydration had a positive effect on the chemical index of lysine, methionine and cysteine, leucine and tryptophan. However, the nutritional quality of sorghum grain proteins and derivatives obtained, evaluated according to the chemical index, is low. The results obtained reported that dehulling and hydrothermal treatment unevenly altered the amino acid content, and the method of boiling grains with pre-hydration had a positive effect on the CSI of lysine, methionine and cysteine, leucine and tryptophan.

Implications of multipurpose tree leaf application on wheat productivity in dry tropics

Leaves of multipurpose tree species （those providing more than one function or product of human use） can serve as sources of fer- tilizer for nutrient supply, especially nitrogen （N）. In this study chopped leaves of tropical tree species （5 N-fixing species, 5 non-N-fixing species and combinations of 5 N-fixing with a non-N-fixing species） were in- corporated in soil to evaluate its effects on wheat biological productivity （including grain yield, GyIELD） under dryland conditions. High quality leaves of N-fixing tree species （e.g. Dalbergia sissoo, Cassia fistula and Prosopis cineraria） had lower carbon/nitrogen （C/N）, lignin/nitrogen （L^o/N）, polyphenol/nitrogen （PPt/N） and lignin＋polyphenol /nitrogen （L~＋PpL/N） ratios than low quality leaves of non-N-fixing species. Com- bination treatments had intermediate values of different parameters, Application of high quality leaves caused greater increases in wheat productivity and yield than other species.

Geochemical Characterization of Organic Rich Black Rocks of the Niutitang Formation to Reconstruct the Paleoenvironmental Settings during Early Cambrian Period from Xiangxi Area,Western Hunan,China

The Niutitang Formation in the South China Block might be a source of hydrocarbon as it contains an enormous quantity of organic matter.Black rock of the Early Cambrian Niutitang Formation is widely distributed in the Yangtze region,but detailed geochemical understanding of it is still emerging.This research discusses the detailed geochemical characteristics of the Niutitang Formation to reconstruct the paleoenvironmental conditions,employing total organic carbon(TOC)content,major,trace,and rare earth element data.For this purpose,black rock specimens of the Niutitang Formation from two outcrop sections were utilized for geochemical characterization,and the results compared with another eight sections from the South China Block.The average total organic carbon in these sediments is significantly higher(5.80 wt.%).In the platform region,lower quantities of TOC indicate a poor potential to produce hydrocarbons.At the same time,significantly higher TOC is observed in the deep shelf and slope sediments,indicating a significant potential to produce hydrocarbons.The average Ce,Eu and Y anomalies from both Longbizui and Sancha sections studied are 0.74,0.86,1.77,1.07,and 1.19,1.30,respectively.The chemical index of alteration(CAI)throughout the Yangtze block is higher(averaging 71.32)than that of Post Archean Australian Shale(PAAS 69),indicating a moderately weathered source of the Niutitang Formation relative to PAAS.As the sediments are moderately weathered,this suggests these rocks might have been derived from felsic rocks,mainly granite-granodiorite.The normalization of REEs in the black rocks reveals a reduction of light REEs with increase in heavy REEs enrichment.Similarly,a positive Eu anomaly,negative Ce anomaly,and a moderate Y/Ho(34.61)are clues to a hybrid depositional mechanism associated with hydrothermal action and terrigenous input.These anomalies are also evidence of upwelling in the paleo-ocean and mixing of organic matter,which created anoxic bottom water during the deposition of the Niutitang Formation in the basin and upper oxic water conditions before deposition.The main controlling factors for the distribution of rare earth elements in these black rocks of the Niutitang Formation are pH,terrigenous input,source rock composition,tectonism,an upwelling mechanism,and hydrothermal activity.

Sedimentary and geochemical evidence of Eocene climate change in the Xining Basin, northeastern Tibetan Plateau

The northeastern Tibetan Plateau began to grow during the Eocene and it is important to understand the climatic history of Asia during this period of so-called ‘doubthouse' conditions. However, despite major advances in the last few decades,the evolutionary history and possible mechanisms of Eocene climate change in the northeastern Tibetan Plateau remain unclear.The Xining Basin in the northeastern Tibetan Plateau contains a continuous sequence of Early to Late Eocene non-marine sediments which provides the opportunity to resolve long-term climate changes during this period. In this study, we report the results of analyses of lithofacies, sediment color and geochemistry of bulk samples collected from the Xijigou section of the Xining Basin. An abrupt lithofacies change between the Early(~52–40 Ma) and Late Eocene(~40–34 Ma) indicates a change in the depositional environment from a shallow lake to a playa lake in response to a significant climatic shift. During ~52–40 Ma,higher values of sediment redness(a*), redness/lightness(a*/L*) and higher modified Chemical Index of Weathering(CIW′)indicate a relatively warm and humid climate, while from ~40–34 Ma the lower values of a*, a*/L*and lower CIW′ imply subhumid to semi-arid climatic conditions. The paleoclimatic records indicate a long-term(~52–34 Ma) trend of decreasing chemical weathering, consistent with global climate change. An abrupt sharp excursion of the proxy records during ~42–40 Ma suggests a relatively brief warm interval, corresponding to the Middle Eocene Climatic Optimum(MECO). We suggest that global cooling substantially reduced humidity in inner Asia, resulting in sub-humid to semi-arid climatic conditions after 40 Ma in the Xining Basin, which may have been responsible for the long-term trend of decreasing chemical weathering during the Eocene.

Neoproterozoic sedimentary facies and glacial periods in the southwest of Tarim Block

Based on the analysis of sedimentary facies and chemical index of alteration(CIA) in Nanhua and Ediacaran Systems in the southwest of Tarim Block,some features of glacial records in Neoproterozoic become more clear.Six sedimentary facies have been divided in the study area,including alluvial fan facies,lacustrine facies,glacial facies,littoral facies,neritic facies,and lagoonal facies,showing that this area underwent a process from continent to marine,with mainly littoral and neritic sedimentation.Two cold events have been recognized by analysis of CIA values in the study area,called Bolong and Yutang glaciation,respectively.They present as thick-layer tillite deposition in the Bolong Formation and thin-layer tillite deposition in the Yutang Formation,respectively.The Bolong glacial period in the study area can be correlated to the Yulmeinak glacial period in Aksu area,Tereeken glacial period in Qurugtagh area,and the Nantuo glacial period in South China,which is equivalent to the universally acknowledged Marinoan glacial period.The Yutang glacial period can be correlated to the Hankalchough glacial period in Qurugtagh,which is equivalent to Gaskers glaciation in Newfoundland.