Application of Calcium Sulfate Whiskers to Cement-Based Materials: A Review.

In recent years, significant attention has been paid to the use of calcium sulfate whiskers (CSWs) to enhance the performance of cement-based materials (CBM). This technology has attracted widespread interest from researchers because it enhances the performance and sustainability of CBM by modifying the crystal structure of calcium sulfate. This article summarizes the fundamental properties and preparation methods of calcium sulfate whisker materials as well as their applications in cement, potential advantages and disadvantages, and practical applications and prospects. The introduction of CSWs has been demonstrated to enhance the strength, durability, and crack resistance of CBM while also addressing concerns related to permeability and shrinkage. The application of this technology is expected to improve the quality and lifespan of buildings, reduce maintenance costs, and positively impact the environment. The use of CSWs in CBM represents a promising material innovation that offers lasting and sustainable advancement in the construction industry.

Functional Characterization of CsSWEET5a, a Cucumber Hexose Transporter That Mediates the Hexose Supply for Pollen Development and Rescues Male Fertility in Arabidopsis.

Pollen cells require large amounts of sugars from the anther to support their development, which is critical for plant sexual reproduction and crop yield. Sugars Will Eventually be Exported Transporters (SWEETs) have been shown to play an important role in the apoplasmic unloading of sugars from anther tissues into symplasmically isolated developing pollen cells and thereby affect the sugar supply for pollen development. However, among the 17 CsSWEET genes identified in the cucumber (Cucumis sativus L.) genome, the CsSWEET gene involved in this process has not been identified. Here, a member of the SWEET gene family, CsSWEET5a, was identified and characterized. The quantitative real-time PCR and ß-glucuronidase expression analysis revealed that CsSWEET5a is highly expressed in the anthers and pollen cells of male cucumber flowers from the microsporocyte stage (stage 9) to the mature pollen stage (stage 12). Its subcellular localization indicated that the CsSWEET5a protein is localized to the plasma membrane. The heterologous expression assays in yeast demonstrated that CsSWEET5a encodes a hexose transporter that can complement both glucose and fructose transport deficiencies. CsSWEET5a can significantly rescue the pollen viability and fertility of atsweet8 mutant Arabidopsis plants. The possible role of CsSWEET5a in supplying hexose to developing pollen cells via the apoplast is also discussed.

Single-cell multi-omics analysis of human testicular germ cell tumor reveals its molecular features and microenvironment.

Seminoma is the most common malignant solid tumor in 14 to 44 year-old men. However, its molecular features and tumor microenvironment (TME) is largely unexplored. Here, we perform a series of studies via genomics profiling (single cell multi-omics and spatial transcriptomics) and functional examination using seminoma samples and a seminoma cell line. We identify key gene expression programs share between seminoma and primordial germ cells, and further characterize the functions of TFAP2C in promoting tumor invasion and migration. We also identify 15 immune cell subtypes in TME, and find that subtypes with exhaustion features were located closer to the tumor region through combined spatial transcriptome analysis. Furthermore, we identify key pathways and genes that may facilitate seminoma disseminating beyond the seminiferous tubules. These findings advance our knowledge of seminoma tumorigenesis and produce a multi-omics atlas of in situ human seminoma microenvironment, which could help discover potential therapy targets for seminoma.

CSNK1G2-AS1 promotes metastasis, colony formation and serves as a biomarker in testicular germ cell tumor cells.

Background/Aim: Some long non-coding RNAs (lncRNAs) have been found to significantly participate in the progression of TGCTs. In comparison to the normal testis, the TGCT tissues showed significantly decreased CSNK1G2-AS1 expression, however, its effect on TGCTs and its mechanism are still unclear. The aim of this study is to investigate the effect of CSNK1G2-AS1 on TGCTs and explore the mechanism underlying its effect on TGCTs. Materials and Methods: In this study, to evaluate the expression of CSNK1G2-AS1 in tissue samples from TGCTs, the UCSC and GEPIA databases were applied and qRT-PCR was conducted. The Kaplan-Meier Plotter was applied to analyze the correlation between CSNK1G2-AS1 methylation levels and the prognosis of TGCTs patients. The assays of MTS, clone formation, transwell, and flow cytometry were performed to investigate the effect of CSNK1G2-AS1 overexpression on the proliferation, metastasis, and apoptosis of TGCT cells, respectively. Finally, western blotting was conducted to determine the expressions of the proteins associated with EMT and AKT. Results: Our study first found that, compared to the normal testis, TGCTs tissue showed significantly decreased CSNK1G2-AS1 expression, and hypomethylation of CSNK1G2-AS1 was significantly correlated with a better prognosis with TGCTs patients. In vitro, we found that overexpression of CSNK1G2-AS1 dramatically promoted the clone formation, invasion, and migration of TGCT cells, but inhibited apoptosis. And CSNK1G2-AS1 overexpression significantly decreased the expression of EMT-associated proteins ZO-1 but increased the expression and phosphorylation of AKT. Conclusions: CSNK1G2-AS1 may play an essential role in the pathogenesis and metastasis of TGCTs through the EMT- and AKT-mediated signal pathways.

A low carbon management model for regional energy economies based on blockchain technology.

As the issue of sustainable energy development becomes more and more important in national economic construction, the potential dangers of climate change are gradually attracting widespread attention from countries around the world. In order to better carry out the low-carbon management of the regional energy economy, based on the analysis of the characteristics of blockchain technology, the present study utilized this technology to achieve intelligent and digital management of carbon emissions, and established a carbon emission prediction system. The cuckoo algorithm is used to improve the long-term memory network, and the improved algorithm is used in carbon emission prediction and management. The experimental results show that the improved Long Short Term Memory networks are close to the target precision in 240 iterations, and the convergence speed is fast. In the short-term regional carbon emission prediction, the average absolute error of the method is only 2%, which is highly consistent with the actual carbon emission. In the long-term carbon emission prediction, the average prediction accuracy of the upgraded long-term short-term memory networks can reach 97.26%, and the running time is only 19.46s. With high precision and running efficiency, the upgraded Long Short Term Memory networks can efficiently monitor regional carbon emission and provide a technical reference for the low-carbon management of the regional power industry.

Prediction of Anthocyanidins Content in Purple Chinese Cabbage Based on Visible/Near Infrared Spectroscopy.

Purple Chinese cabbage (PCC) has become a new breeding trend due to its attractive color and high nutritional quality since it contains abundant anthocyanidins. With the aim of rapid evaluation of PCC anthocyanidins contents and screening of breeding materials, a fast quantitative detection method for anthocyanidins in PCC was established using Near Infrared Spectroscopy (NIR). The PCC samples were scanned by NIR, and the spectral data combined with the chemometric results of anthocyanidins contents obtained by high-performance liquid chromatography were processed to establish the prediction models. The content of cyanidin varied from 93.5 mg/kg to 12,802.4 mg/kg in PCC, while the other anthocyanidins were much lower. The developed NIR prediction models on the basis of partial least square regression with the preprocessing of no-scattering mode and the first-order derivative showed the best prediction performance: for cyanidin, the external correlation coefficient (RSQ) and standard error of cross-validation (SECV) of the calibration set were 0.965 and 693.004, respectively; for total anthocyanidins, the RSQ and SECV of the calibration set were 0.966 and 685.994, respectively. The established models were effective, and this NIR method, with the advantages of timesaving and convenience, could be applied in purple vegetable breeding practice.

Structural Design and Research Progress of Thermally Conductive Polyimide Film - A Review.

Currently, heat accumulation has seriously affected the stabilities and life of electronic devices. Polyimide (PI) film with high thermal conductivity coefficient (λ) has long been held up as an ideal solution for heat dissipation. Based on the thermal conduction mechanisms and classical thermal conduction models, this review presents design ideas of PI films with microscopically ordered liquid crystalline structures which are of great significance for breaking the limit of λ enhancement and describes the construction principles of thermal conduction network in high-λ filler strengthened PI films. Furthermore, the effects of filler type, thermal conduction paths, and interfacial thermal resistances on thermally conductive behavior of PI film are systematically reviewed. Meanwhile, this paper summarizes the reported research and provides an outlook on the future development of thermally conductive PI films. Finally, it is expected that this review will give some guidance to future studies in thermally conductive PI film.

High-Fat Diet Aggravates the Disorder of Glucose Metabolism Caused by Chlorpyrifos Exposure in Experimental Rats.

Epidemiological research has demonstrated that the increase in high fat consumption has promoted the morbidity of diabetes. Exposure to organophosphorus pesticides (such as chlorpyrifos) may also increase the risk of diabetes. Although chlorpyrifos is a frequently detected organophosphorus pesticide, the interaction effect between chlorpyrifos exposure and a high-fat diet on glucose metabolism is still unclear. Thus, the effects of chlorpyrifos exposure on glucose metabolism in rats eating a normal-fat diet or a high-fat diet were investigated. The results demonstrated that the glycogen content in the liver decreased and that the glucose content increased in chlorpyrifos-treated groups. Remarkably, the ATP consumption in the chlorpyrifos-treatment group was promoted in the rats eating a high-fat diet. However, chlorpyrifos treatment did not change the serum levels of insulin and glucagon. Notably, the contents of liver ALT and AST changed more significantly in the high-fat chlorpyrifos-exposed group than in the normal-fat chlorpyrifos-exposed group. Chlorpyrifos exposure caused an increase in the liver MDA level and a decrease in the enzyme activities of GSH-Px, CAT, and SOD, and the changes were more significant in the high-fat chlorpyrifos-treatment group. The results indicated that chlorpyrifos exposure led to disordered glucose metabolism in all dietary patterns as a result of antioxidant damage in the liver, in which a high-fat diet may have aggravated its toxicity.

Glucoraphanin Accumulation via Glucoraphanin Synthesis Promotion during Broccoli Germination.

Glucoraphanin is an important glucosinolate which is widely distributed in Brassica vegetables and poses an anticancer effect to humans. Although researchers have paid a lot of attention to the changes in glucoraphanin concentration in seedlings of broccoli over 1-2 weeks, there has been little research focusing on the total whole-sprout glucoraphanin content within broccoli seedlings over 1-5 weeks. However, it is necessary to clarify the changes in total glucoraphanin content during the broccoli sprouting stage as broccoli seedlings are novel plant foods. This research explored glucoraphanin absolute accumulation and the biosynthesis mechanism in broccoli seedlings during a 5-week growth period. The results showed that glucoraphanin accumulation content was higher at week 4 than in the seeds. Moreover, the relative DL-methionine contents increased significantly after 3 weeks. Glucoraphanin synthetic gene expression levels were increased after 3 weeks, but the gene expressions of AOP3 (encoding 2-oxoglutarate-dependent dioxygenases) and MYR (encoding myrosinase) were significantly decreased. Furthermore, the 20 essential DEGs obtained can provide new insight into understanding the developmental regulation of broccoli seedlings. In addition, the results can also provide information on how to obtain higher glucoraphanin contents in broccoli sprouts.

Microorganisms-An Effective Tool to Intensify the Utilization of Sulforaphane.

Sulforaphane (SFN) was generated by the hydrolysis of glucoraphanin under the action of myrosinase. However, due to the instability of SFN, the bioavailability of SFN was limited. Meanwhile, the gut flora obtained the ability to synthesize myrosinase and glucoraphanin, which could be converted into SFN in the intestine. However, the ability of microorganisms to synthesize myrosinase in the gut was limited. Therefore, microorganisms with myrosinase synthesis ability need to be supplemented. With the development of research, microorganisms with high levels of myrosinase synthesis could be obtained by artificial selection and gene modification. Researchers found the SFN production rate of the transformed microorganisms could be significantly improved. However, despite applying transformation technology and regulating nutrients to microorganisms, it still could not provide the best efficiency during generating SFN and could not accomplish colonization in the intestine. Due to the great effect of microencapsulation on improving the colonization ability of microorganisms, microencapsulation is currently an important way to deliver microorganisms into the gut. This article mainly analyzed the possibility of obtaining SFN-producing microorganisms through gene modification and delivering them to the gut via microencapsulation to improve the utilization rate of SFN. It could provide a theoretical basis for expanding the application scope of SFN.

Characterization of the Volatile Compounds of Onion with Different Fresh-Cut Styles and Storage Temperatures.

The flavor of fresh onion and its processed products is an important index with which to evaluate its quality. In this study, the highly volatile compounds of onion with different fresh-cut styles (bulb, ring, and square) and different storage temperatures (4 °C, 20 °C, and 25 °C) were characterized at the molecular level, focusing in particular on the volatile sulfur compounds. Headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) and headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) were employed. A total of 14 highly volatile compounds were identified in onion samples by HS-GC-IMS, and the square sample contained more volatile components. (E,E)-2,4-heptadianal, ethyl acetate, 2-methyl-1-pentanol, 2-pentylfuran, propyl acetate, and 2,6-dimethylpyrazine were produced in the ring and square samples when stored at higher temperatures, while pentanal, 2-heptenal, hexanal were decreased after cutting. Simultaneously, 16 sulfur compounds were identified in onions by HS-SPME-GC-MS. The sulfur compounds profile of the bulbs was significantly different from that of the rings and squares at any temperature. When stored at a low temperature (4 °C), cutting onions into a ring or square shape produced more sulfur. However, at higher temperatures (20 °C and 25 °C), fresh-cutting decreased the sulfur concentration. The total content of sulfur compounds was higher in the same cut style stored at higher temperatures (20 °C or 25 °C). 2-Mercapto-3,4-dimethyl-2,3-dihydrothiophene and 2,4-dimethylthiophene were formed during storage; however, (E)-1-(prop-1-en-1-yl)-3-propyltrisulfane, 1-(1-(methylthio)propyl)-2-propyldisulfane, (Z)-1-(1-propenyldithio)propyl disulfide, dipropyl trisulfide, and methyl 1-(1-propenylthio)propyl disulfide were lost from all samples after storage.

Effects of nanocarbon solution treatment on the nutrients and glucosinolate metabolism in broccoli.

The effects of a nanocarbon solution on the nutrients, glucosinolate metabolism and glucoraphanin pathway in broccoli were investigated. Significant positive linear relationships were observed between the nanocarbon solution and total protein yield, although effects on the soluble sugars, vitamin C and dry matter production were not observed. All nanocarbon solutions significantly increased the glucoraphanin content (p < 0.05), and the 18.75 L·ha-1 nanocarbon solution maximally increased the glucoraphanin content by 22.9 %. However, these treatments also significantly reduced the contents of glucobrassicin, 4-methoxyglucobrassicin, 4-hydroxyglucobrassicin and neoglucobrassicin. Further research demonstrated that the 18.75 L·ha-1 nanocarbon solution significantly upregulated the MAM1, IPMI2, CYP79F1, FMOgs-ox2, AOP2, and TGG1 expression levels, which directly resulted in the accumulation of glucoraphanin and glucoerucin. This study provides insights into the prospective nanotechnological approaches for developing efficient and environmentally friendly nanocarbon solution for use on crops.

Allicin Promoted Reducing Effect of Garlic Powder through Acrylamide Formation Stage.

BACKGROUND: Acrylamide is formed during food heating and is neurotoxic to animals and potentially carcinogenic to humans. It is important to reduce acrylamide content during food processing. Researchers have suggested that garlic powder could reduce acrylamide content, but the key substance and acrylamide reduction pathway of garlic powder was unclear. METHODS: The inhibitory effect of garlic powder on acrylamide in asparagine/glucose solution and a fried potato model system were firstly evaluated. Furthermore, the effect of allicin on the amount of produced acrylamide in the asparagine/glucose solution model system and fried potatoes was studied with kinetic analysis. RESULTS: The freeze-dried garlic powder had a higher inhibition rate (41.0%) than oven-dried garlic powder (maximum inhibition rate was 37.3%), and allicin had a 71.3% attribution to the reduction of acrylamide content. Moreover, the inhibition rate of allicin had a nonlinear relationship with the addition level increase. The kinetic analysis indicated that garlic powder and allicin could reduce acrylamide content through the AA formation stage, but not the decomposition stage. CONCLUSIONS: Allicin was the key component of garlic powder in reducing acrylamide content during acrylamide formation stage. This research could provide a new method to reduce acrylamide content during food processing and expand the application area of garlic.

CsSWEET2, a Hexose Transporter from Cucumber (Cucumis sativus L.), Affects Sugar Metabolism and Improves Cold Tolerance in Arabidopsis.

Sugars, which are critical osmotic compounds and signalling molecules in plants, and Sugars Will Eventually be Exported Transporters (SWEETs), which constitute a novel family of sugar transporters, play central roles in plant responses to multiple abiotic stresses. In the present study, a member of the SWEET gene family from cucumber (Cucumis sativus L.), CsSWEET2, was identified and characterized. Histochemical analysis of ß-glucuronidase expression in transgenic Arabidopsis plants showed that CsSWEET2 is highly expressed in the leaves; subcellular localization indicated that CsSWEET2 proteins are localized in the plasma membrane and endoplasmic reticulum. Heterologous expression assays in yeast demonstrated that CsSWEET2 encodes an energy-independent hexose/H+ uniporter that can complement both glucose and fructose transport deficiencies. Compared with wild-type Arabidopsis plants, transgenic Arabidopsis plants overexpressing CsSWEET2 had much lower relative electrolyte leakage levels and were much more resistant to cold stress. Sugar content analysis showed that glucose and fructose levels in the transgenic Arabidopsis plants were significantly higher than those in the wild-type plants. Taken together, our results suggest that, by mediating sugar metabolism and compartmentation, CsSWEET2 plays a vital role in improving plant cold tolerance.

Integrated analysis of high-throughput sequencing data reveals the key role of LINC00467 in the invasion and metastasis of testicular germ cell tumors.

Long noncoding RNAs (lncRNAs) are involved in various physiological and pathological processes. However, the role of lncRNAs in testicular germ cell tumor (TGCT) has been rarely reported. Our purpose is to comprehensively survey the expression and function of lncRNAs in TGCT. In this study, we used RNA sequencing to construct the lncRNA expression profiles of 13 TGCT tissues and 4 paraneoplastic tissues to explore the function of lncRNAs in TGCT. The bioinformatics analysis showed that many lncRNAs are differentially expressed in TGCT. GO and KEGG enrichment analyses revealed that the differentially expressed lncRNAs participated in various biological processes associated with tumorigenesis in cis and trans manners. Further, we found that the expression of LINC00467 was positively correlated with the poor prognosis and pathological grade of TGCT using WGCNA analysis and GEPIA database data mining. In vitro experiments revealed that LNC00467 could promote the migration and invasion of TGCT cells by regulating the expression of AKT3 and influencing total AKT phosphorylation. Further analysis of TCGA data revealed that the expression was negatively correlated with the infiltration of immune cells and the response to PD1 immunotherapy. In summary, this study is the first to construct the expression profile of lncRNAs in TGCT. It is also the first study to identify the metastasis-promoting role of LNC00467, which can be used as a potential predictor of TGCT prognosis and immunotherapeutic response to provide a clinical reference for the treatment and diagnosis of TGCT metastasis.

Evolutionary gain of oligosaccharide hydrolysis and sugar transport enhanced carbohydrate partitioning in sweet watermelon fruits.

How raffinose (Raf) family oligosaccharides, the major translocated sugars in the vascular bundle in cucurbits, are hydrolyzed and subsequently partitioned has not been fully elucidated. By performing reciprocal grafting of watermelon (Citrullus lanatus) fruits to branch stems, we observed that Raf was hydrolyzed in the fruit of cultivar watermelons but was backlogged in the fruit of wild ancestor species. Through a genome-wide association study, the alkaline alpha-galactosidase ClAGA2 was identified as the key factor controlling stachyose and Raf hydrolysis, and it was determined to be specifically expressed in the vascular bundle. Analysis of transgenic plants confirmed that ClAGA2 controls fruit Raf hydrolysis and reduces sugar content in fruits. Two single-nucleotide polymorphisms (SNPs) within the ClAGA2 promoter affect the recruitment of the transcription factor ClNF-YC2 (nuclear transcription factor Y subunit C) to regulate ClAGA2 expression. Moreover, this study demonstrates that C. lanatus Sugars Will Eventually Be Exported Transporter 3 (ClSWEET3) and Tonoplast Sugar Transporter (ClTST2) participate in plasma membrane sugar transport and sugar storage in fruit cell vacuoles, respectively. Knocking out ClAGA2, ClSWEET3, and ClTST2 affected fruit sugar accumulation. Genomic signatures indicate that the selection of ClAGA2, ClSWEET3, and ClTST2 for carbohydrate partitioning led to the derivation of modern sweet watermelon from non-sweet ancestors during domestication.

Determination of 18 Intact Glucosinolates in Brassicaceae Vegetables by UHPLC-MS/MS: Comparing Tissue Disruption Methods for Sample Preparation.

Glucosinolates (GSLs) are important precursor compounds with anticancer activities in Brassicaceae vegetables and are readily hydrolyzed by myrosinase. Given the diversity of these species, establishing an accurate and universal method to quantify intact GSLs in different plant tissues is necessary. Here, we compared and optimized three tissue disruption methods for sample preparation. After microwave treatment for 90 s, 13 GSLs in homogenized Chinese cabbage samples were recovered at 73-124%. However, a limitation of this method was that different tissues could not be processed under the same microwave conditions. Regarding universality, GSLs in Brassicaceae vegetables could be extracted from freeze-dried sample powder with 70% methanol (v/v) or frozen-fresh sample powder with 80% methanol (v/v). Moreover, heating extraction is necessary for GSLs extracted from frozen-fresh sample powder. Average recoveries of the two optimized methods were 74-119% with relative standard deviations ≤ 15%, with the limits of quantification 5.72-17.40 nmol/g dry weight and 0.80-1.43 nmol/g fresh weight, respectively. Notably, the method for analyzing intact GSLs was more efficient than that for desulfo-GSLs regarding operational complexity, detection speed and quantification accuracy. The developed method was applied to identify the characteristic GSLs in 15 Brassicaceae vegetables, providing a foundation for further research on GSLs.

SPANXN2 functions a cell migration inhibitor in testicular germ cell tumor cells.

BACKGROUND: SPANX family members are thought to play an important role in cancer progression. The SPANXN2 is a gene expressed mainly in normal testis, but its role in testicular germ cell tumors (TGCTs) has yet to be investigated. TGCT is one of the most common solid tumors in young men and is associated with poor prognosis; however, effective prognostic indicators remain elusive. Therefore, we investigated the role of SPANXN2 in TGCT development. METHODS: SPANXN2 expression levels were validated by quantitative real-time polymerase chain reaction (qRT-PCR) analyses of 14 TGCT samples and five adjacent normal tissue samples. SPANXN2 was transiently overexpressed in TGCT cells to study the consequences for cell function. The effects of SPANXN2 on cell migration were evaluated in transwell and wound healing assays. The effects on cloning ability were evaluated in colony formation assays. MTT assays and cell cycle analysis were used to detect the effects of SPANXN2 on cell proliferation. The expression levels of EMT- and AKT-related proteins in cells overexpressing SPANXN2 were analyzed by Western blotting. RESULTS: Compared with adjacent normal tissues, the Gene Expression Profiling Interactive Analysis database showed SPANXN2 expression was downregulated in TGCTs which was consistent with the qRT-PCR analysis. SPANXN2 overexpression reduced cell migration and colony formation capability and downregulated expression of EMT- and AKT-related proteins, Vimentin, Snail, AKT, and p-AKT. CONCLUSION: Our results suggest that SPANXN2 regulates TGCT cell migration via EMT- and AKT-related proteins although its role in the occurrence and development of TGCT remains to be fully elucidated.

Enhanced visible light photocatalytic activity of N, F-codoped TiO2 powders with high thermal stability.

Doping non-metals onto TiO2 has been regarded as a promising way to gain a more effective photocatalyst. In this paper, N, F-codoped TiO2 was synthesized by the sol-gel method, demonstrating both high adsorption capacity and high photocatalytic activity under visible light irradiation. Samples were characterized by X-ray diffraction, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy and UV-visible diffuse reflectance spectra (UV-vis DRS). The results show that N, F-codoping can reduce the impact of calcination temperature on the structure and morphology of the sample, resulting in the sample exhibiting good thermal stability, even when the calcination temperature changes in a large range, instead of rutile, the anatase around 20 nm is the only phase in N, F-codoped samples. It can be clearly observed from the SEM images that N, F-codoped samples calcined at different temperatures are in the state of scattered particles with small size and good dispersed property. And it is vivid that the absorption intensity of N, F-codoped TiO2 samples in the visible light range increases substantially in DRS. According to the result of photocatalytic activity experiment, N, F-codoped TiO2 samples calcined at 973 K exhibited the highest degradation rate for Methylene Blue.

Release and kinetics of arsenic and plumbum in the Songhua River surficial sediments.

To estimate the pollution of As and Pb in the Songhua River which flows through the major rice-producing regions in China, the present study investigated the level and release of As and Pb in surficial sediments which collected from nine sites in Songhua River (M1-M9). The concentration of As and Pb was ranged as follows: As = 3.104~15.01 µg/g, Pb = 20.10~37.42 µg/g; the average concentration: As = 6.466 ± 3.077 µg/g, Pb = 28.88 ± 5.077 µg/g. By analysis vertically, the average concentration of As was 5.166 ± 1.496 µg/g in the upstream, 5.815 ± 1.793 µg/g in the midstream, and 9.716 ± 4.977 µg/g in the downstream. The average concentration of Pb was 27.83 ± 4.552 µg/g in the upstream, 28.66 ± 6.333 µg/g in the midstream, and 30.99 ± 4.837 µg/g in the downstream. It indicated that the concentration of As and Pb increased gradually from upstream to downstream. As existed mainly as insoluble state and Pb existed mainly as sulfide and organic combining state in surficial sediments, and the species of As and Pb could transform with the change of the circumstance. The release of quantity of As was higher than Pb. The pH of 6 was not conducive to the release of As and Pb. When the temperature was 35 and 6 °C, the release of As and Pb in surficial sediments were restrained, respectively. Fumaric acid and citric acid played an important role in promoting the release of As, but not conducive to Pb. Furthermore, the reasonable aeration rate was beneficial to the release process of As and Pb in surficial sediment. By kinetic analysis, the Elovich equation (Ct = 84.931-8.952lnt) could be used to describe the dynamic process of the release of As in a relatively short time. The Elovich equation (C t  = 2.724 + 1.3724lnt) and double constant rate equation (lnC T  = 1.4646 + 0.1522lnT) could well describe the dynamics process of the release of Pb.