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Roasting is an important step in the pretreatment of biomass upgrading. Roasting can improve the fuel quality of biomass, reduce the O/C and H/C ratios in the biomass, and provide the biomass with a fuel quality comparable to that of lignite. Therefore, studying the structure and component evolution laws during biomass roasting treatment is important for the rational and efficient utilization of biomass. When the roasting temperature is 200–300 °C, the cellulose and hemicellulose in the biomass undergo a depolymerization reaction, releasing many monocyclic aromatic hydrocarbons with high reactivity. The proportion of monocyclic aromatic hydrocarbons in biomass roasting products can be effectively regulated by controlling the reaction temperature, residence time, catalyst, baking atmosphere, and other factors in the biomass roasting process. This paper focuses on the dissociation law of organic components in the pretreatment process of biomass roasting.

It is great significance to understand the mechanism of heat transfer deterioration of supercritical CO2 for heat exchanger design and safe operation in the supercritical CO2 Brayton cycle. Three-dimensional steady-state numerical simulation was performed to investigate the behavior of supercritical CO2 heat transfer in heated vertical up-flow tube with inner diameter di = 10 mm and heated length Lh = 2000 mm. Based on the characteristics of inverted-annular film boiling at subcritical pressure, the heat transfer model of supercritical CO2 flowing in the heated vertical tube was established in this paper. The mechanisms of heat transfer deterioration (HTD) and heat transfer recovery (HTR) for supercritical CO2 were discussed. Numerical results demonstrate that HTD is affected by multiple factors, such as the thickness and property of vapor-like film near the wall, the turbulence intensity near the interface between liquid-like and vapor-like, and in the liquid-like core region as well as the distribution of radial velocity vector. Among the above factors, the change of turbulent kinetic energy caused by the buoyancy effect seems to be a more important contributor to HTD and HTR. Furthermore, the influences of heat flux and mass flux on the distribution of wall temperature were analyzed, respectively. The reasons for the difference in wall temperature at different heat fluxes and mass fluxes were explained by capturing detailed thermal physical properties and turbulence fields. The present investigation can provide valuable information for the design optimization and safe operation of a supercritical CO2 heat exchanger.

Organic electrochemical transistors (OECTs) are of great interest in low‐power bioelectronics and neuromorphic computing, as they utilize organic mixed ionic‐electronic conductors (OMIECs) to transduce ionic signals into electrical signals. However, the poor environmental stability of OMIEC materials significantly restricts the practical application of OECTs. Therefore, the non‐fused planar naphthalenediimide (NDI)‐dialkoxybithiazole (2Tz) copolymers are fine‐tuned through varying ethylene glycol (EG) side chain lengths from tri(ethylene glycol) to hexa(ethylene glycol) (namely P‐XO, X = 3–6) to achieve OECTs with high‐stability and low threshold voltage. As a result, the NDI‐2Tz copolymers exhibit ambipolarity, rapid response (<10 ms), and ultra‐high n‐type stability. Notably, the P‐6O copolymers display a threshold voltage as low as 0.27 V. They can operate in n‐type mode in an aqueous solution for over 60 h, maintaining an on‐off ratio of over 105. This work sheds light on the design of exceptional n‐type/ambipolar materials for OECTs. It demonstrates the potential of incorporating these ambipolar polymers into water‐operational integrated circuits for long‐term biosensing systems and energy‐efficient brain‐inspired computing. Four NDI‐2Tz copolymers (P‐XO, X = 3–6) with modified EG side chains are synthesized. They exhibit exceptional n‐type operational stability (over 60 h) in OECTs, fast switching (<10 ms), and excellent ambipolar behavior. Increasing the length of side chains enhances the hydrophilicity of the materials, thereby boosting electrochemical doping efficiency. This study reveals EG substitution's impact on NDI‐2Tz copolymers, providing insight for stable, low‐power n‐type/ambipolar materials.

The design of heat exchangers in the advanced supercritical power conversion system cannot be separated from the study of heat transfer issues. Half-side heating mode is often encountered for solar receiver and supercritical boiler. Here, the characteristics of supercritical CO 2 (sCO 2 ) convection heat transfer in vertical tubes with circumferentially half-side heating was numerically investigated through the SST k-ω turbulent model which matches well with the experimental data. Then, heat transfer between sCO 2 upflow and downflow was compared. Similar to film boiling heat transfer at subcritical pressure, numerical results were processed according to the supercritical pseudo-phase transition hypothesis, with liquid-like phase in the tube core region and vapor-like film in the region near the heated tube wall. The structure of two layers was demarcated by pseudo-critical temperature T pc . Therefore, sCO 2 heat transfer was assessed according to double thermal resistances caused by vapor-like film near the wall and core liquid-like phase. The findings suggest that wall temperature for upflow is higher than that for downflow, which is attributed to larger thermal resistance in the fluid domain for upflow than that for downflow. The difference guarantees the excellent heat transfer performance for downflow than upflow. It is also further concluded that the formation of vapor-like film near the wall due to pseudo-phase transition plays a key role in dominating wall temperature and inducing heat transfer deterioration in half-side heating tubes. The present contribution is significant to the design of supercritical heat exchanger under half-side heating mode.

It is great significance to understand the mechanism of heat transfer deterioration of supercritical CO for heat exchanger design and safe operation in the supercritical CO Brayton cycle. Three-dimensional steady-state numerical simulation was performed to investigate the behavior of supercritical CO heat transfer in heated vertical up-flow tube with inner diameter d = 10 mm and heated length L = 2000 mm. Based on the characteristics of inverted-annular film boiling at subcritical pressure, the heat transfer model of supercritical CO flowing in the heated vertical tube was established in this paper. The mechanisms of heat transfer deterioration (HTD) and heat transfer recovery (HTR) for supercritical CO were discussed. Numerical results demonstrate that HTD is affected by multiple factors, such as the thickness and property of vapor-like film near the wall, the turbulence intensity near the interface between liquid-like and vapor-like, and in the liquid-like core region as well as the distribution of radial velocity vector. Among the above factors, the change of turbulent kinetic energy caused by the buoyancy effect seems to be a more important contributor to HTD and HTR. Furthermore, the influences of heat flux and mass flux on the distribution of wall temperature were analyzed, respectively. The reasons for the difference in wall temperature at different heat fluxes and mass fluxes were explained by capturing detailed thermal physical properties and turbulence fields. The present investigation can provide valuable information for the design optimization and safe operation of a supercritical CO heat exchanger.

Boiler tube leakage is the major reason of affecting the safe operation of the unit now, there are 3 methods of the \"four tube\" leakage detection: Traditional method, filtering method and acoustic spectrum analysis, acoustic spectrum analysis is the common method, but this method have low sensitivity and the sensor damage easily. Therewith, designed the special acoustic catheter with acoustic resonance cavity type, proved by experiments, the acoustic catheter with acoustic resonance cavity type can enhance leakage sound, can accurately extract leakage signals, has high sensitivity, and can avoid the effect of sensor by fire and hot-gas when the furnace is in positive pressure situation, reduce the installation and maintenance costs of the boiler tube leakage monitor system.

目的 探讨茵陈蒿汤对阻塞性黄疸大鼠肾氧化应激损伤的作用与调节核因子E2相关因子2(Nrf2)表达及核异位的关系。 方法 32只雄性SD大鼠，随机分为假手术组(S组)、模型组(O组)、低剂量茵陈蒿汤组(LY组)和高剂量茵陈蒿汤组(HY组)，每组8只，S组大鼠仅游离上段胆总管但不予结扎，剩余各组大鼠胆总管中上1/3行双重结扎建立阻塞性黄疸模型，7天后LY组、HY组分别予茵陈蒿汤6.3 mL/kg和18.9 mL/kg灌胃，S组、O组每日给予等体积蒸馏水灌胃，连续7天，于第14天处理大鼠。采用ELISA法测定大鼠血清总胆红素(TBil)、直接胆红素(DBil)、丙氨酸转氨酶(ALT)、谷氨酰转移酶(GGT)、尿素氮(BUN)和血肌酐(Cr)水平；分光光度法检测大鼠肾组织氧化应激因子超氧化物歧化酶(SOD)和丙二醛(MDA)活性；实时荧光定量PCR和蛋白免疫印迹法分别检测肾组织中Nrf2、Kelch样环氧氯丙烷相关蛋白1(Keap1)、醌氧化还原酶1(NQO1)mRNA和蛋白表达水平；免疫组化检测肾组织中Nrf2蛋白的核异位情况。计量资料多组间比较采用单因素方差分析，组内进一步两两比较采用LSD-t检验。 结果 与S组比较，O组大鼠TBil、DBil、ALT、GGT、BUN、Cr水平升高，SOD活性减弱，MDA水平升高，差异均有统计学意义(P值均＜0.05)；与O组比较，LY组和HY组肝、肾功能指标水平均下降，SOD活性升高，MDA水平降低，差异均有统计学意义(P值均＜0.05)。与S组比较，O组大鼠肾组织中Nrf2、NQO1 mRNA和蛋白表达水平均明显下降(P值均＜0.05)；与O组比较，LY组和HY组Nrf2、NQO1 mRNA和蛋白表达水平均明显升高(P值均＜0.05)；各组大鼠肾组织中Keap1蛋白表达水平无明显差异(P＞0.05)。与S组比较，O组大鼠肾组织中Nrf2细胞核内阳性率显著降低(P＜0.05)；与O组比较，LY组和HY组Nrf2细胞核内阳性率均显著升高(P值均＜0.05)。 结论 茵陈蒿汤可以有效减轻阻塞性黄疸引起的肾损伤，其作用机制可能是通过上调大鼠肾组织中Nrf2蛋白的表达，并调控Nrf2蛋白核异位，从而介导下游NQO1蛋白的表达，调节阻塞性黄疸引起的氧化应激反应，进而减轻大鼠肾损伤。

P736.4; 硬石膏是最早构成热液烟囱体壁的矿物之一,其对于了解流体-海水混合以及海底热液系统中元素的迁移与循环具有重要的意义.为此,对西太平洋冲绳海槽唐印热液区中的硬石膏,进行了微区原位元素以及硫同位素组成分析.根据硬石膏的结晶形态,可以将硬石膏分为两种类型:较早形成的I型硬石膏,其呈半自形或他形晶,似针状、放射状及不规则晶的集合体产出;较晚形成的II型硬石膏,其呈自形晶,以板状及粒状晶的集合体产出.当热液流体初次遇到海水时,将快速沉淀形成I型硬石膏,并构成了热液烟囱体的壁.随后,II型硬石膏经历了一个相对充分的生长阶段.同时,硬石膏中的Ba、Al、Sr、Ni、Fe、Mn和Cr含量明显高于海水,表明产生硬石膏沉淀的热液流体来自于海底面以下,是经历了流体-岩石和/或沉积物相互作用的流体.硬石膏的Mg含量明显分别低于海水和高于喷口流体,表明其是流体-海水混合的结果.I型硬石膏,其Sr含量明显低于II型硬石膏,表明在形成自形、板片状或粒状硬石膏的期间,来自热液流体的Sr,主要进入II型硬石膏中.硬石膏的Fe、As、Sr、Ba和Pb含量,明显高于冲绳海槽喷口流体的,则表明这些来自流体中的元素更容易随着硬石膏的沉淀而进入硬石膏中,并导致硬石膏富集该类元素.硬石膏的稀土元素组成及其配分模式,具正Ce和负Eu异常的特征,其是流体在海底面以下从火山岩和/或沉积物中淋滤出来,并经历了流体-海水混合作用的结果.此外,在流体-海水混合期间,硬石膏中的硫主要来自海水.

对采自6个种源地砂生槐的种子进行了萌发研究,分析了种子大小、萌发特性与海拔之间的关系.结果表明：1）每荚种子数变幅为2.96～4.50粒;种子千粒质量变幅为30.639～47.415 g;种子纵径变幅为4.314～4.962mm;种子横径变幅为3.244～3.693 mm;种子纵横径比变幅为1.306～1.383,差异较小.方差分析结果显示,种源间每荚种子数（F=8.52＊＊）、千粒质量（F=19.73＊＊）、种子纵径（F=6.17＊＊）和种子横径（F=5.79＊＊）差异均达到极显著水平,而种子纵径与横径的比值差异不显著（F=1.47）.2）6个种源砂生槐种子发芽率变幅为43.16％～90.03％.其中萨迦种源发芽率90.03％为最高,最低是米瑞种源为43.16％.3）6个砂生槐种源的种子在发芽起始时间上仅差异1d;萌发持续时间在14～23 d之间,种源间持续发芽时间差异最多达到9d;萌发高峰期在17～27 d之间,种源间差异较大,其中萨迦种源最短,朗县种源最长.4）每荚种子数随着海拔的升高而显著降低（R=-0.844 3,P＜0.05）,而种子千粒质量则随着海拔的升高而显著升高（R =0.614 3,P＜0.05）.5）种子发芽起始时间与海拔之间呈现出负相关的关系,但不显著（R=-0.505 6,P＞0.05）;种子萌发持续时间与海拔具有显著的负相关关系（R=-0.883 6,P＜0.05）,而种子发芽率则与海拔具有显著的正相关关系（R=0.804 7,P＜0.05）.

研究海底热液系统及其岩浆环境，可为了解西太平洋流固界面跨圈层物质与热交换过程，揭示板块俯冲过程的岩浆活动和资源环境效应提供研究支撑。为此，研究了冲绳海槽热液活动的岩浆环境、马努斯海盆的热液柱以及弧后盆地和洋中脊背景下的硫化物与玄武岩的同位素组成，对冲绳海槽热液区附近玄武岩、安山岩、粗安岩、英安岩、流纹岩及其基性岩浆包体进行了岩相学、矿物学以及主量元素、微量元素和同位素组成分析，对马努斯海盆PACMANUS和Desmos热液区的热液柱及海水进行了测量，在海底热液区岩浆混合过程及时间尺度、透视冲绳海槽深部岩浆房及岩浆演化过程和岩浆对热液系统物质贡献研究方面获新进展，揭示了俯冲蛇纹岩对琉球构造带南部岩浆活动的影响，论证了熔体包裹体对弧后盆地岩浆演化的指示，获得了冲绳海槽玄武质岩浆来源新证据，揭示了弧后盆地与洋中脊硫化物和玄武岩中铁、铜、锌的来源及其同位素在硫化物形成和岩浆活动过程中的分馏情况，明确了热液柱的物理、化学空间结构与物质组成特征，以及热液柱的扩散受深度和底流流速的影响，且热液柱扩散过程中溶解铁浓度异常比溶解锰的维持时间更长。未来，发展非传统稳定同位素和挥发份测试技术，进一步了解西太平洋板块俯冲环境下热液活动与岩浆作用的关系，将有助于海底热液系统及其成矿过程研究获得新进展。