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Copyright of Acta Scientiarum Naturalium Universitatis Pekinensis is the property of Editorial Office of Acta Scientiarum Naturalium Universitatis Pekinensis and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the rapid expansion of the scale of nuclear energy, the proper treatment of radioactive waste generated by the nuclear industry has become one of the most important issues for the further development of nuclear energy. Cyclodextrin, as a kind of cyclic oligosaccharide composed of several glucopyranose units, has a good prospect of application in the field of radioactive ions adsorption and separation, because of its special molecular structure of internal hydrophobicity and external hydrophilicity. However, due to the presence of a large number of hydroxyl groups in the cyclodextrin molecules, they are easily soluble in water. Generally, the solidification of cyclodextrins to insoluble solids is always needed before being used as adsorption materials. Depending on the different methods of " solidification", cyclodextrin based adsorbent materials can be divided into three types: loaded cyclodextrin materials, cyclodextrin polymer materials, and cyclodextrin inclusion complex materials. The synthesis and application research advances of the three types of cyclodextrin adsorbent materials in radioactive ion adsorption and separation are summarized, the related adsorption mechanisms are discussed. Besides, the perspectives of the cyclodextrin based adsorbents in the field of radioactive ion adsorption are presented. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Drainage & Irrigation Machinery Engineering / Paiguan Jixie Gongcheng Xuebao is the property of Editorial Department of Drainage & Irrigation Machinery Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The worm-like micelles formed by the mixture of an anionic surfactant (sodium a-olefin sulfonate, AOS) and a zwitterionic surfactant (lauramidopropyl hydroxysulfobetaine, LHSB) as induced by Mn ions were studied. The influencing factors studied included the mass ratio between the two surfactants, the mass fraction of Mn, the mass fraction of surfactants, and the temperature. The results showed that, the viscosity of the surfactant solution first increased and then decreased as the mass ratio of AOS : LHSB was increased and the mass fraction of Mn2+ was increased. The zero-shear viscosity of the system exhibited an exponential increase with increasing mass fraction of surfactants. The viscosity measurement was conducted at 25 °C. The maximum viscosity was obtained when the mass ratio of AOS : LHSB was 3 : 7, and the optimal Mn content was 0.5% when the mass fraction of surfactants was 2% (the zero-shear viscosity at this optimal condition was measured to be 9 030.9 mPa·s). The morphology of the micelles in solution was observed using Cryo-TEM, revealing long worm-like micelles with a tight network structure and good linear viscoelasticity. The mass fraction of surfactants and the presence of Mn were found to have significant influence on the formation of worm-like micelles. This study could provide important additional information for the preparation of worm-like micelles using mixed anionic-zwitterionic surfactant system. [ABSTRACT FROM AUTHOR]

While the existing university chemistry experimental teaching content is comprehensive, it often lacks a connection with cutting-edge scientific research, particularly in trending fields. In this study, we introduce the experiment "Kaempferol as an AIE-active natural product probe for selective Al3+ detection" into teaching practice. Through this experiment, students gain an understanding of the contributions made by Chinese scientists in the field of aggregation-induced emission (AIE) research. They also learn about the fundamental principles and applications of fluorescence, and gain intuitive insights into the distinctions between aggregation-induced emission and aggregationinduced quenching. The experiment encompasses complex structure analysis, spectral analysis, and instrumental characterization, offering both comprehensiveness and ease of operation. By engaging in this teaching practice, students develop their innovative thinking and comprehensive abilities, while simultaneously reinforcing their commitment to environmentally friendly development and enhancing a sense of national pride. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of Botanical Research is the property of Bulletin of Botanical Research Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Seawater desalination is one of the most promising solutions to fresh water shortage all over the world. The rapid development of nanotechnology led to the boom of nanoporous membranes for water purification. Recent theoretical and experimental studies reported ultra-high water permeability and salt rejection in nanoporous monolayer graphene. However, the difficulty of precisely creating nanometer-scale pores and controlling their distribution greatly limits its industrial application. Through molecular dynamics (MD) simulation, the monolayer quasi-tetragonal phase fullerene (qTPC60) was found to have tremendous potential as ultra-permeable membranes for desalination due to their unform pore distribution. The monolayer fullerene membranes exhibit high water permeability compared to conventional polymer filtration membranes. The work offers insights into the molecular mechanism of sieving, and the MD simulations show that Na+ and Cl- ions have large energy barriers. This 2D monolayer carbon material with unique structure exhibits great potential in seawater desalination. [ABSTRACT FROM AUTHOR]

[Objective] The soil salinization characteristics under different land use types in extremely arid regions were analyzed in order to provide support for the sustainable efficient utilization of regional land resources. [Methods] We used GPS positioning technology to investigate and sample the irrigation water, irrigation drainage, and soil under four typical land use types in the area of Lower Tarm River in different seasons. We combined those data with indoor measurement results to determine the variation characteristics of salinity and salt ions in the irrigation area. [Results] The soil in the study area was alkaline, and the salt type was mainly sulfate-chloride. The salt content was between 2.44 and 118.05 g/kg, and the pH value was between 8.05 and 8.34. The overall changes of soil salt content and pH value under different land use types in each season followed the order of salt wasteland > saline-alkali grassland > cultivated land and forest land. Analysis of samples from different soil depths indicated surface accumulation of salinity in June and October, and no obvious pattern in March and December. There was an obvious surface accumulation of salt in salt wasteland and saline-alkali grassland in different seasons at different soil depths. Forest land had no obvious salt accumulation pattern in each season. Because of the geographical location of the reservoir, the groundwater level in the study area was shallow (1.4—3.51 m), the groundwater salinity was high (1.56—21.30 g/L), and the salt ions in irrigation water and groundwater were mainly Na+ and Cl-. [Conclusion] The soil salinization characteristics under different land use types in the study area were mainly affected by factors such as surface coverage, crop types, and irrigation events. The quality of groundwater and irrigation water was an important factor affecting the soil salt content and salt ion type in the study area. Certain measures should be taken to control the groundwater level and salt content so as to protect existing cultivated land and forest land. The irrigation and drainage water of high salt content from farmland should be discharged to the salt wasteland. In the future, relevant research should be conducted on the spatial configuration of agricultural land and salt wasteland, and the rational allocation of salt discharge land would be conducive to the desalination of farmland.

:To solve the problem that practical applications of devices in the field of moisture generation are limited by complex preparation processes and high material costs, we developed an environmentally friendly, low-cost wood-based moisture generator (W -MEG) by a simple modified process. Firstly, the wood was delignified using a 2. 5% sodium chlorite (NaClO2 ) solution to keep its natural water transport channels open. Secondly, we prepared sodium alginate / reduced graphene oxide (SA/ rGO) hydrogels with excellent moisture absorption and ion diffusion ability and coated them onto the wood surface. Finally, to further improve the power generation performance of the prepared W-MEG, the degree of hydrogel immersion into the internal channels of the wood was controlled by adjusting the time of the reduced pressure impregnation process to form an asymmetric structure with more top and less bottom, which further expanded the ion concentration distribution. Based on this asymmetrical structure, taking advantage of wood's natural directional water transport properties and ion diffusion effects, our W-MEG can generate an open-circuit voltage of 220 mV and a short-circuit current of 0. 28 μA at 80% relative humidity (RH), with a power output in the RH range of 35%-95%. In addition, by integrating multiple W-MEG units, it can be used as an efficient power source to drive miniature commercial devices such as LEDs, which has the potential for practical applications. This study provides new insights into simple, inexpensive and efficient moisture energy harvesting devices and enables novel technologies for the utilization of wood. [ABSTRACT FROM AUTHOR]

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Guangdong University of Technology is the property of Journal of Guangdong University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to reduce the low mass discrimination effect of the miniaturized ion funnel, a method of gradient descent radio frequency (RF) signal application was proposed. The RF signals with decreasing amplitude were applied on the outlet electrodes of the ion funnel, which would improve the transmission efficiency of low mass-to-charge ratio ions. The ion transmission performance of the miniature ion funnel with the gradient descent RF signal applying was studied by simulation software SIMION and ion trajectory simulation software AXSIM. When the gradient descent RF voltage was applied, the potential line around the outlet electrodes of miniaturized ion funnel was sparse, and the effective potential was shallower, then it could significantly reduce the axial effective potential of the terminal electrode. The simulation results showed that the gradient descent RF application method could effectively reduce the low mass discrimination, while the transmission efficiency of high mass ions was not affected. As revealed by the simulation, when the initial RF voltage amplitude V₁ was 120 V and 80 V. respectively, the corresponding optimal descent gradient was 6 V and 3 V. and σ the ion transmission efficiency could achieve 60% and 62% for the ions at m/z 20, while it still maintained nearly 100% efficiency in high mass range (m/z 200). Not only that, at lower mass segments (m/z 20). a lower mass-to-charge ratio cutoff was obtained in the gradient descent RF signal application mode. which demonstrated that this new RF signal application method could significantly extend the low mass range. The influence of RF frequency and direct current (DC) field gradient parameter with the gradient descent RF application method on the ion transmission efficiency was studied in detail, indicating that a RF frequency of 1 MHz and a DC field gradient parameter of 10 V/cm were the optimal value of obtaining a high ion transmission efficiency. Further, the gradient descent RF signal application method was simplified. The ion transfer efficiency achieved by the simplified method decreased slightly, but it was still better than that achieved by the traditional RF application method. An ion transmission efficiency (at m/z 20) of 56.6% was achieved in the simplified gradient descent RF signal application mode, which was decreased by 5. 7% compared with that before simplification and improved by 57. 2% compared to conventional RF application mode. The simulation result illustrated that the simplified gradient descent RF application mode can reduce low mass discrimination effect to adequate extent. The simplification method can reduce the difficulty of operation and improve the feasibility of the scheme implementation. [ABSTRACT FROM AUTHOR]

Due to the composition complexity of traditional Chinese medicines (TCMs). the identification and clarification of the chemical components of TCMs plays a crucial role in the evaluation of safety and efficacy of their clinical use. In this work, an ultra-high performance liquid chromatography-quadrupole-electrostatic field Orbitrap mass spectrometry (UHPLC-Q-Orbitrap/MS) was used to analyze the chemical composition of the substance benchmark of Zhu Ye ShiGao decoction (ZSD), a widely used TCM formula. The UHPLC separation was performed on a SUPELCO C18 column (100 mm X 4.6 mm X 2.7 µm) with water (A) and acetonitrile (B) both containing 0.1% formic acid as mobile phases. The column temperature was 30 °C, and the injection volume was 5 μL. The gradient started with 5% B. and increased to 20% B at 5 min. to 40% B at 15 min, to 95%B at 25 min, dropped back down to 5% B at 27 min, and remained 5%B to 35 min with a flow rate of 0.5 mL/min. The molecular ions and fragment ions data obtained by HRMS in positive and negative ion modes were used to identify the components in the substance benchmark of ZSD by referring to the self-constructed database from the related literatures and the MS data collected from control products, and to study the MS fragmentation mechanism. A total of 121 compounds were identified. including 47 triterpenes. 34 flavonoids. 10 steroidal saponins, and 30 other compounds. Among them, the flavonoids are mainly from Lophatheri, Glycyrrhizae and Ophiopogonis, the saponins are mainly from Ginseng and Glycyrrhizae, and the alkaloids are mainly from Pinelliae. ZSD formula consists of 7 herbs, of which the components may be loss during the preparation of the substance benchmark. For example, the amino acids in Pinelliae was significantly reduced in the substance benchmark, and the wide- spread presence of steroidal saponins in Ophiopogonis was also converted during the preparation. In addition to the loss of components, components in different herbs may react with each another to produce new components during the preparation of the substance benchmark. These not only led to absence of identification of some well- known components in the herbs of ZSD, but also made it difficult to identify the newly produced compounds with high intensity of MS signals, requiring further study. Even so, however, the present work identified the chemical composition of the ZSD substance benchmark and explored the fragmentation pathways of the identified components by using UHPLC-Q-Otbitrap/MS, providing a good reference basis for quality control and the pharmacodynamics research of ZSD. [ABSTRACT FROM AUTHOR]

The adsorption capacity of natural low-methoxy pectin from sunflower heads on heavy metal copper ions (Cu2+) in aqueous solution was studied, and the effects of dosage, pH, adsorption temperature and time, and coexisting ions were investigated. Our results indicated that with increasing the pectin dosage, the removal rate of Cu2+ was continuously increased, whereas the adsorption capacity was initially increased and then decreased. Both adsorption capacity and removal rate increased initially and then remained unchanged with the increase in adsorption temperature or time. Similarly, both increased initially and then decreased with the increase in pH of pectin, whereas they decreased with the increase in concentration of divalent metal ions (coexisting ions) owing to the effect of coexisting ions. When the initial concentration of Cu2+ was in the range of 0~200 mg/L, the Langmuir isothermal equation was used to obtain the maximum Cu2+ adsorption capacity of pectin, which was 29.94 mg/g. Thermodynamic analysis showed that the adsorption process was a spontaneous and endothermic reaction with increasing entropy. Kinetics analysis revealed that the adsorption process followed the pseudo-second-order kinetic equation with electrostatic attraction and complexation as the main driving force. Thus, pectin derived from sunflower heads exhibits a strong Cu2+ sption capacity, making it a viable option as a safe, effective, and eco-friendly biosorption material for the treatment of Cu2+-contaminated wastewater. [ABSTRACT FROM AUTHOR]

This review focuses on the synergistic corrosion inhibition effect of plant corrosion inhibitors and iodide ions in different media in recent years, it summarizes the effects of synergistic plant extracts such as leaves, rods, bark, gum with iodide ions on corrosion inhibition efficiency and the adsorption mechanism of iodide ions on metal. Compared with synthetic organic corrosion inhibitors, environmentally friendly plant・ based corrosion inhib让ors can improve their corrosion inhibition efficiency through synergism, and have gradually become a hot field of research. [ABSTRACT FROM AUTHOR]

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bulletin of Soil & Water Conservation is the property of Bulletin of Soil & Water Conservation Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

【Objective】 Drip irrigation using brackish water is a way to relieve water shortage in arid regions such as Xinjiang, but it needs a good management to reduce its detrimental consequence. The aim of this paper is to investigate the combined effect of irrigation water quality and nitrogen fertigation on changes in soil salinity and Na+ and Ca2+ concentration in soil water with cotton planted. 【Method】 A pot experiment was conducted from June to October 2020 at Alaer in Xinjiang. There are three nitrogen treatments: 255 kg/hm2 (F1), 315 kg/hm2 (F2) and 375 kg/hm2 (F3), and three irrigation water quality treatments: 1.27 g/L (Q1), 3.03 g/L(Q2), 4.90 g/L (Q3). Irrigation with groundwater was taken as the control. In each treatment, we measured soil salt content, and concentration of Na+ and Ca2+ in soil water. 【Result】 Depending on nitrogen fertigation, saline water irrigation increased total soil salt content and Na+ and Ca2+ concentrations by 14%~78%, 42%~197% and 58%~253%, respectively, compared to groundwater irrigation. It also increased soil sodium adsorption ratio (SAR) and exchangeable sodium percentage (ESP) by 5%~109% and 48%~90%, respectively. Increasing nitrogen application to 315 kg/hm2 and 375 kg/hm2 reduced soil salinity and Na+ and Ca2+ concentrations by 11%~70%, 6%~42% and 21%~138%, respectively, and reduced soil SAR and ESP by 5%~27% and 3%~19%, respectively, compared to the control. 【Conclusion】 Soil salinity increased with the increase in irrigation water salinity, but increasing nitrogen application to 315 kg/hm2 could reduce soil salinity and Na+ and Ca2+ concentrations in soil water, thereby alleviating salinity stresses.

Copyright of Journal of Dalian University of Technology / Dalian Ligong Daxue Xuebao is the property of Journal of Dalian University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bulletin of the Chinese Ceramic Society is the property of Bulletin of the Chinese Ceramic Society Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food & Machinery is the property of Food & Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Atmosphere is a complex mixture system including various gaseous molecules and particulate matters as well as free radicals. The cases of atmospheric pollution often occur in urban or suburban areas during the evolution of industry, and have adverse influences on the human health and daily life. The origins of atmospheric pollution are complicated, which often comprise a series of chemical reactions involving abundant volatile organic compounds (VOCs), free radicals and aerosol particles. How to analyze these species operando is a hot, significant and challenging topic of atmospheric chemistry. In the past decades, benefiting from the rapid development of analytical techniques used in the atmospheric chemistry, abundant reaction mechanisms for the formation of pollutants have been proposed and revealed. However, due to the complexity of atmospheric chemistry, presently the formation mechanisms of atmospheric pollution are still very limited or coarse and deserve to be comprehensively investigated. As a widely used analytical technique, vacuum ultraviolet photoionization mass spectrometry (VUV-PIMS) can provide mass information of molecular ions benefiting from its “soft” ionization at the threshold ionization energy of molecules. Therefore, the obtained VUV photoionization mass spectra have the characters of no or less fragment ions and are easier to be assigned. Then the key chemical components involved in the atmospheric chemical reactions can be identified efficiently, which are very helpful to reveal the complex mechanisms of atmospheric chemical reactions. In this paper, the recent development of VUV-PIMS and its wide applications in atmospheric chemistry were summarized. Several kinds of VUV light sources, including VUV laser, synchrotron radiation, free electron laser and VUV discharge lamp, were presented. In combination with these advanced light sources, several kinds of VUV-PIMS setups were introduced and their advantages were discussed. In addition, the applications of VUV-PIMS to analyze atmospheric VOCs, free radicals and their reactions, and the chemical compositions of aerosol particles were reviewed. Concretely, in the aspect to detect VOCs in laboratory or on site, several strategies to improve the sensitivity of detection, in particular the improvement of the photoionization source, were presented here in detail. The analysis of several elusive free radicals and their atmospheric oxidation reactions studied by VUV-PIMS were described. Then, the utilization of VUV-PIMS to measure the chemical compositions of aerosols was introduced. Moreover, the perspectives of VUV-PIMS and its further applications in atmospheric chemistry were also discussed. [ABSTRACT FROM AUTHOR]

Copyright of Hydrometallurgy of China is the property of Hydrometallurgy of China Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An on-line pyrolysis-vacuum ultraviolet photoionization mass spectrometer was built for the analysis of pyrolysis products of tobacco. Vacuum ultraviolet photoionization is a “soft” ionization method producing few or no fragments of molecular ions, and identifing the complex pyrolysis products in real time. In this work, the pyrolysis of tobacco leaves from various stalk positions (B2 F, C3 F and X2 F) at 300, 400, 500, 600 and 700 ℃, and the effects of reaction temperature on the pyrolysis products intensity were studied. A series of mass spectra of pyrolysis products were obtained, and the changes of products at different pyrolysis temperatures were compared. The analysis results of products at different pyrolysis temperatures were helpful to reveal the formation mechanism of compounds in different parts of cut tobacco during pyrolysis/combustion. The dynamic curves of pyrolysis products such as vinylamine (m/z 43), isoprene (m/z 68) and dimethylfuran (m/z 96) with time were further observed at 500 ℃, so as to master the dynamic change process of pyrolysis reaction. It was found that the increase of temperature can dramatically shorten the reaction time. Generally, the primary products will be formed at the medium cracking temperature, and gradually pyrolyzed into secondary products with the increase of temperature, the secondary products will be accompanied by higher temperature cracking and thermal synthesis to form tertiary products. In order to quickly screen and identify different parts of tobacco, principal component analysis (PCA) was used to analyze the mass spectra of pyrolysis products, and the differences of chemical components in different parts of tobacco were identified. Then, the components with m/z 58, 96, 110 were the typical products of X2 F, the components with m/z 43, 126 were the representative products of C3 F, and the main representative product of B2 F was the component with m/z 84. Based on the above results, photoionization mass spectrometry was important to study the dynamic changes of tobacco pyrolysis products, the pyrolysis products of different parts of tobacco were quickly identified at 300-700 ℃, and the main pyrolysis products were summarized. By comprehensively evaluating the main components and relative content of pyrolysis products, tobacco samples from different parts can be quickly distinguished. [ABSTRACT FROM AUTHOR]

A double potential well flat ion trap was designed as an ion accumulating and focusing device for multi-reflection time-of-flight mass analyzer. Two potential wells of the trap were severally used for accumulation of injected ions, controlled cooling and ejection of trapped ions, which had features to accumulate ions continuously and cool ion for almost one period. While a flat ion trap with only one potential well is a traditional and excellent ion accumulating and focusing device, which has an intermittent ion accumulation and an ion cooling around half period. Compared with the single potential well flat ion trap, the double potential well flat ion trap had better performance on ion accumulation and focusing in principle. Four steps to run the trap were simulated and researched by an ion optics simulator of SIMION 8.1. The first step was ion accumulation, ions were successively injected into the trap, and then stored and accumulated in the first potential well. The second step was ion transfer, the trapped ions were transferred from the first potential well to the second potential well. The third step was ion cooling, the trapped ions were confined in the second potential well, and were simultaneously cooled by collisions with 0.5 Pa He. The fourth step was ion ejection, the trapped ions were ejected from the trap and focused into the next device. Ion optics simulations indicated that the trap had a period from 1 ms to above 10 ms, a total ion transmission efficiency of 83%, and an ion flux of at most 1.6×106 ions. In addition, ion packets ejected from the trap had thermalized with radial diameters of 1.0 and 1.0 mm, angular standard deviations of 24 mrad and 16 mrad, and an energy standard deviation of 15 eV. This trap can be coupled with and provide high-flux and full-focusing ion packets for multi-reflection time-of-flight mass analyzers, due to an excellent suitability between the operation of the analyzer and the period, the ion transmission efficiency, the ion flux, and ejected ion packets of the trap. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Chalcopyrite is often associated with some impurity minerals such as pyrite, quartz, carbonateand silicate minerals, and the presence of these minerals will affect the leaching of chalcopyrite. Additionally, to promote the dissolution of chalcopyrite, some oxidants often need to be added in its leaching process, which generates manyunavoidable ions. Therefore, involving the ions produced from the dissolution of impurity minerals will affect the leaching efficiency of chalcopyrite.In this paper, the effect of the typical impurity minerals and ions on chalcopyrite dissolution was reviewed for providinga theoretical foundation for the high-efficiency and complete CuFeS2 leaching.

With the rapid development of modern detection technology and scientific research, the chemical structures and functions of isomers are constantly being revealed. The isomer molecules may have completely different biochemical activities, and a certain molecule of the isomer may play an important role in disease pathogenesis or disease treatment, while the other is the opposite. Therefore, the separation and identification of isomers and the exploration of their structures are helpful to furtherly understand the operating mechanism of life, and become one of the research hotspots in the field of analytical chemistry and life sciences. Ion mobility spectrometry (IMS), which has developed rapidly in recent years, is an instrument technology that can analyze the spatial structure of molecules. It can distinguish the isomerism of a certain molecule by measuring the difference in the collision cross-section between different molecular ions and airflow in the gas phase. IMS coupled with mass spectrometry (IMS-MS) is a powerful separation and analysis technology that adds a mobility separation dimension for MS to improve ion structure separation and determination, while also enhances ion mass selection in mobility technology and makes the separation of the analyte have high selectivity. IMS-MS technology has been highly concerned and widely used in the fields of small molecule/metabolite identification, proteomics research, host-guest complexes, and molecular structure identification. This paper was focused on the working principle of different types of IMS, the latest application in different types of isomers and the prospect of IMS-MS. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Based on the progress of ionic liquids in the synthesis of molecular sieve materials in recent years, the mechanism of ionic thermal synthesis of molecular sieve, the synthesis of new molecular sieve and the innovation of synthetic method are discussed ・ The unique properties and unique synthetic environment of ionic liquid have great advantages in the field of new molecular sieve synthesis. It is expected that ion thermal synthesis will have more room for development in the field of molecular sieve material synthesis. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The sodium ion layered oxide cathode material NaNi0.4Mn0.4Fe0.2O2 was synthesized by the co-precipitation method， and Al3+was used to effectively control and balance the co-precipitation reaction process. The thermodynamic coupling effect brought by the addition of Al element and its influence on electrochemical performance of cathode materials were investigated. In an environment where Mn2+， Ni2+ and Fe3+ ions coexist， owing to the thermodynamic coupling effect， the superior high supersaturation of Al3+ and the more negative change in the Gibbs free energy(ΔG)can efficiently changes the precipitation driving force between the solution ions， accelerating the precipitation of Ni2+and Mn2+ ions and inhibiting the precipitation of Fe3+ ions. The obtained Na[Ni0.4Mn0.4Fe0.2]0.995Al0.005O2 cathode material has demonstrated excellent electrochemical performance which can be attributed to the high quality precursor(［0.4MnCO3·0.4NiCO3·0.2Fe(OH)3］0.995·0.005Al(OH)3) brought about by the introduction of Al3+. [ABSTRACT FROM AUTHOR]

Copyright of Writing / Xiezuo is the property of Writing Magazine Agency, Wuhan University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Test & Measurement Technology is the property of Publishing Center of North University of China and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Test & Measurement Technology is the property of Publishing Center of North University of China and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aiming at the shortcomings of small specific surface area of g-C3N4, fast recombination o£ photogenerated carriers and low utilization efficiency o£ visible light, the modification methods of g-C3N4 are described, including morphology adjustment, ion doping, and semiconductor recombination, aiming to increase the specific surface area. To speed up the separation of electron-hole pairs and broaden the visible light response range; at the same time, the influence of the corresponding modification methods on the photocatalytic performance is discussed, so as to achieve the purpose of improving the photocatalytic performance; finally, the future development trend of g-C3 N4 is carried out outlook. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Chinese Journal of Explosives & Propellants is the property of Chinese Journal of Explosives & Propellants Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: To analyze the correlation between the changes in salivary ion concentration, Streptococcus and Bifidobacterium in children with dental caries and the severity of the disease., Methods: Eighty children with dental caries treated from May 2022 to April 2023 were selected as the experimental group. According to the DMFT, they were divided into mild group (DMFT≤15%, n=35) and severe group (DMFT>15%, n=45). Another 80 children without dental caries were selected as the control group. The calcium ion concentration in saliva was detected by methanol-permeabilized calciometric method, the level of Streptococcus and Bifidobacterium was detected by real-time single-quantity PCR technology, and the correlation between DMFT and salivary calcium ion concentration, Streptococcus and Bifidobacterium was analyzed by Pearson correlation analysis. The diagnostic value of salivary calcium ion concentration, Streptococcus and Bifidobacterium for the severity of dental caries in children was evaluated by the receiver operating characteristic curve(ROC), and the area under the curve(AUC) was calculated. SPSS 22.0 software package was used for statistical analysis., Results: The level of salivary calcium ion concentration, Streptococcus mutans, Streptococcus sobrinus and Bifidobacterium in the experimental group was significantly higher than that in the control group(P＜0.05), and significantly higher in the severe group than in the mild group(P＜0.05). DMFT was significantly positively correlated with salivary calcium ion concentration, Streptococcus and Bifidobacterium (P＜0.05). Based on DMFT, ROC curve was prepared, and AUCs of salivary calcium ion concentration, Streptococcus mutans, Streptococcus sobrinus and Bifidobacterium for assessing the severity of dental caries in children were 0.760, 0.658, 0.718 and 0.705, respectively., Conclusions: Increased salivary ion concentration, Streptococcus sobrinus, Streptococcus mutans and Bifidobacterium levels are related to dental caries in children, and are positively correlated with the severity of the disease, which has a certain value for assessing the severity of the disease.