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采用核磁共振(NMR)技术对山西省内生产的亚麻籽油进行脂肪酸组成检测及品质鉴别。首先运用气相色谱-质谱联用(GC-MS)法确认纯亚麻籽油和掺杂亚麻籽油脂肪酸组成的差异；然后通过核磁共振谱仪确认差异核磁共振氢谱（1H NMR）和碳谱（13C NMR）的特征峰，以快速判别亚麻籽油是否掺杂；最后，采用1H NMR法计算亚麻籽油中的脂肪酸含量，并与国标GC法进行对比。结果表明：与纯亚麻籽油相比，掺杂亚麻籽油中含有花生一烯酸和芥酸；通过花生一烯酸和芥酸1H NMR和13C NMR特征峰可以定性鉴别亚麻籽油是否掺杂；采用1H NMR法计算的亚麻籽油中亚麻酸含量与GC法一致。说明基于NMR技术对亚麻籽油脂肪酸组成进行检测，可以快速鉴别亚麻籽油品质。 The fatty acid composition and quality identification of linseed oil produced in Shanxi province were studied by nuclear magnetic resonance (NMR). Firstly, gas chromatography-mass spectrometry (GC-MS) method was used to detect and confirm the difference in fatty acid composition between pure linseed oil and adulterated linseed oil. Secondly, the characteristic peaks of the different fatty acids in the adulterated linseed oil were identified by the hydrogen nuclear magnetic resonance spectrum (1H NMR) and carbon nuclear magnetic resonance spectrum (13C NMR) so as to quickly determine whether the linseed oil was adulterated. Finally, the contents of fatty acids in linseed oil were quantitatively calculated by 1H NMR method and national standard GC method, respectively. The results showed that compared with the pure linseed oil, the adulterated linseed oil contained eicosenoic acid and erucic acid; the 1H NMR and 13C NMR characteristic peaks of eicosenoic acid and erucic acid could be used to qualitatively identify whether linseed oil was adulterated; the content of linolenic acid in linseed oil calculated by 1H NMR method was consistent with that by GC method. The detection of fatty acid composition in linseed oil based on NMR technology can quickly identify the quality of linseed oil.

n-3多不饱和脂肪酸（n-3 PUFA）具有多种生理活性，其主要有3种存在形式，其中甘油酯型n-3 PUFA因其生物利用度高和不易被氧化而优于游离型和乙酯型。然而，目前鲜有对甘油酯型n-3 PUFA进行高纯度富集的方法。为了对甘油酯型n-3 PUFA的高值化更加深入的研究提供参考，综述了富集甘油酯型n-3 PUFA的3种常见方法（物理一步法、两步法和酶一步法）及优缺点。物理一步法可以避免产物氧化，但得率较低；两步法工艺复杂，并有可能产生环境污染；而酶一步法具有简单、高效等优点，成为学者们关注的焦点。现有脂肪酶对甘油酯型n-3 PUFA的富集能力有限，还需进一步发掘富集能力更强的选择性脂肪酶 There are three main forms of n-3 polyunsaturated fatty acids (n-3 PUFA) with a variety of physiological activities, of which glyceride-type n-3 PUFA is superior to free and ethyl ester forms due to its high bioavailability and less susceptibility to oxidation. However, there is few method for the enrichment of glyceride-type n-3 PUFA with high purity. In order to provide a reference for a more in-depth study of the high value of glyceride-type n-3 PUFA, three common methods (physical one-step, two-step and enzymatic one-step), and their advantages and disadvantages of enriching glyceride-type n-3 PUFA were reviewed. The physical one-step method can avoid product oxidation, but the yield is low; the two-step method is complicated and may produce environmental pollution; while the enzymatic one-step method has the advantages of simplicity and high efficiency, which has become the focus of scholars attention. The existing lipases are limited in their ability to enrich glyceride-type n-3 PUFA, and there is a need to further explore selective lipases with higher enrichment capacity.

Based on the Flory - Huggins theory, we built a theoretical model to study the role of co- nonsolvency in the volume phase transition of polymer gel(PG) in co- nonsolvent (CNS). The theoretical model considers the bridging effect of CNS in PG and the miscibility effects of various molecules. We found that when the attraction strength between CNS and polymer monomer is low, the bridging effect between CNS and polymer monomer is weakened, which will lead to the volume phase transition of PC. When the attraction between CNS and polymer monomer is strong, with the weakening of the bridging between CNS and polymer monomer, the volume fraction of PG presents two step transitions, indicating that the PC presents two volume transitions. Because of the weakening of the bridging effect, although some CNS molecules will be squeezed out of the gel, the bridging attraction between CNS and polymer monomer has not been completely eliminated. The theoretical results are consistent with the experimental observations, which indicates that the phase transition behavior of PG can be con- trolled to a large extent by the co-nonsolvency. [ABSTRACT FROM AUTHOR]

The rational planning of land use in rural residential areas is of great significance for balancing the contradiction between urban and rural land use. Taking Zhangjiajie City as an example, geographic information system (GIS) analysis methods were first used to analyze the spatial differentiation characteristics of rural residential areas. Secondly, 14 indicators related to location, transportation, natural environment, and socio-economic aspects, such as distance to highways, rivers, schools, hospitals, elevation, temperature, and precipitation, were selected. The future land-use simulation (FLUS) model was then used to predict the land use status for 2025, 2030, and 2035 under natural development scenarios. Finally, the land use data for rural residential areas in 2030 were extracted, and the ant colony optimization (ACO) algorithm was used for spatial layout optimization based on the geographical simulation and optimization systems (GeoSOS) platform. Quantitative analysis of landscape patterns was conducted before and after optimization, and recommendations were provided. The results show these as follows. In recent years, the land use of rural residential areas in Zhangjiajie City has increased but the degree of aggregation has decreased, showing a distinct “dense in the central and eastern parts, sparse in the northwestern parts” differentiation characteristic, with significant fragmentation, indicating the need for scientific and rational planning. The distribution density of rural residential areas in Zhangjiajie City is in the order of Yongding District > Cili County > Wulingyuan District > Sangzhi County, and the layout patterns can be divided into clustered, strip-shaped, scattered, and clustered patterns according to their basic forms. The FLUS model predicted that the scale of rural residential areas in 2025, 2030, and 2035 tended to stabilize after expansion, with local density growth but overall density changes not significant, and the shape was relatively simple compared to other land use types. After optimization, the overall layout of rural residential areas tended to concentrate in flat areas, with the form showing “overall aggregation and local dispersion”. The results can provide technical support for regional rural land use layout planning. [ABSTRACT FROM AUTHOR]

Based on the Flory-Huggins theory, we built a theoretical model to study the phase transition behavior of zwitterionic polymer (ZP) brushes regulated by hydration and pH. The theoretical model takes into account the hydration of ZP, as well as the electrostatic effect in the ZP brush system. We found that the volume fraction of ZP brushes increases with the weakening hydration under different pH conditions. With the change of pH, the conformation of the ZP brush changes significantly with the hydration transition behavior, which is due to the excessive net charge（positive or negative） of the pH-regulated ZP chain segment, which results in electrostatic repulsion within the ZP chain and ZP brush swells. In addition, when the ZP chain segment presents too much net charge, it will largely determine the electrostatic potential of the ZP brush system and affect the phase transition behavior of the ZP brush. By investigating the free energy of the system, we also found that the free energy of the ZP brush system shows a maximum value. With the change of pH value, the maximum value of the free energy shows a change, indicating the instability of the system. And then, this leads to a phase transition in the ZP brush system. [ABSTRACT FROM AUTHOR]

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为了研究箱形节点域翼缘双削弱(double reduced beam section,DRBS)工字形柱弱轴连接节点的抗震性能,设计了两个系列模型。应用有限元软件Abaqus对第2个削弱区段的长度和深度的取值进行了研究,分析了节点的破坏形式、等效塑性应变、承载力、延性、塑性转动能力及耗能系数等,并与箱形节点域翼缘削弱(reduced beam section,RBS)型弱轴连接节点进行了对比分析。结果表明:在循环荷载作用下,在第2个削弱区段的削弱长度等于第1个削弱区段长度且第2个削弱区段的削弱深度取值宜略大于美国FEMA-350规范推荐的上限值时,箱形节点域DRBS型节点具有良好的抗震性能。与RBS型节点相比,DRBS型节点的承载力降低不明显,但是显著降低了最大等效塑性应变,提高了节点的延性和塑性转动能力。此外,DRBS型节点减缓了梁腹板和翼缘的局部屈曲的发生,从而提高了节点的累积耗能能力。

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Lithium-ion batteries are widely used in various fields due to their superior energy storage performance.However, with the increase of using time, the aging of lithium-ion batteries is prone to lead to different failure degrees,so online fault diagnosis for lithium-ion batteries is crucial. To improve the accuracy and transparency of fault diagnosis,this paper proposes a fault diagnosis model based on continuous probability distribution Evidential Reasoning（ER）rule, and optimizes the related parameters by optimization method. Firstly, this paper extracts characteristic indicators that can reflect batteries’ state of health（SOH） from charging and discharging process, and using Spearman correlation coefficient to analyse the correlation between characteristic indicators and the SOH to extract health indexes. Secondly,considering the uncertainty of battery fault information, propose a fault diagnosis method based on continuous probability distribution reference points of evidential reasoning（ER） rule, the reference points are described by gaussian distribution to achieve online fault diagnosis. Thirdly, designing a whale optimization algorithm（WOA） with constraints to optimize evidence parameters to construct the GER-W fault diagnosis model, so that the accuracy of model fault diagnosis reached the best. Finally, analysing SOH to divide the fuzzy faults, and the effectiveness of the GER-W model is verified by taking the NASA battery data set as an example. In addition, the model is extended to batteries’ SOH estimation. The verification results show that GER-W model has higher accuracy and more transparent process than other fault diagnosis methods, and it also has a certain effect in SOH estimation. [ABSTRACT FROM AUTHOR]

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Slag is one of the main by-products of domestic waste incineration process. It not only has engineering properties comparable to those of natural stone commonly used in road engineering, but also has the hydration properties of cementitious materials, which has received high attention in the field of road engineering materials and solid waste resource utilization, and has gradually developed into an emerging green construction material. This paper reviews the microscopic morphology and structure, leaching characteristics and basic properties of slag, shows the feasibility of slag as a pavement aggregate, and presents the current problems faced by slag aggregates to achieve large-scale applications. [ABSTRACT FROM AUTHOR]

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Caijiaping Pb-Zn deposit in Shangrao of Jiangxi province, is the latest discovered Pb-Zn deposit in Tongboshan Mesozoic continental volcanic basin in the northern Wuyishan metallogenic belt in recent years. Based on field geological survey, the geological characteristics of Caijiaping Pb -Zn deposit are analyzed by means of borehole exposure, rock-ore identification and U-Pb isotopic dating of ore-forming rhyolite porphyry. The results show that the deposit can be divided into subvolcanic type and interlayer fracture belt type, and the genesis of the deposit is closely related to the rhyolite porphyry. The SHRIMP zircon U-Pb age of ore-forming rhyolite porphyry body is 133±3 Ma, the diagenesis and mineralization age of rhyolite porphyry is Early Cretaceous. Comprehensive analysis of regional geology shows that the ore deposit is similar to Lengshuikeng Pb-Zn -Ag polymetallic deposit in terms of its age of rock formation and metallogenic conditions, and has a high potential for prospecting [ABSTRACT FROM AUTHOR]

[Objective] Studying the coordinated development evolution and driving mechanism of coal development and ecosystem services is of great sign ificance for promoting the sustainable development of re source-based cities in China. Methods] Based on the life cycle theory of coal cities, and analysis on the coordinated development and evolution pattern of coal development and ecosystem services, the coordination degree model and gray correlation model were used to reveal the temporal variation and main driving factors of the coordination degree of coal development and ecosystem services in Huainan from 2005 to 2018. --Results] The comprehensive level of coal development in Huainan City showed a fluctuating upward trend, and the comprehensive index of ecosystem services showed a slow downward trend during the study period. The coordination degree of coal development and ecosystem services in Huainan City was basically between ().5 and ().7 from 2005 to 201 8, which showed an upward trend, gradually transitioning from barely coordinated coal mining lag to coordinated synchronous development stage. Environmental pollution governing, residents' living environment demand and industrial transformation were the main driving factors for the coordinated development of coal development and ecosystem services in Huainan City. The correlation degrees of environmental pollution governing, residentsz living environment demand and industrial transformation with the coordinated development were ().91() 2, ().817 8 and 0.807 0, respectively. Conclusion] The study proposed the evolution law of coordinated development of coal development and ecosystem services in coal resource-based cities, revealed the evolution trend and driving mechanism of coordinated development of coal development and ecosystem services in Huainan City, which can provided deci si on-making basis for coordinated and sustain able development of economy and environment in coal resource-based cities. [ABSTRACT FROM AUTHOR]

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