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Frequent freezing injury greatly influences winter wheat production; thus, effective prevention and a command of agricultural production are vital. The freezing injury monitoring method integrated with ‘3S’ (geographic information systems (GIS), global positioning system (GPS) and remote sensing (RS)) technology has an unparalleled advantage. Using HuanJing (HJ)-1A/1B satellite images of a winter wheat field in Shanxi Province, China plus a field survey, crop types and winter wheat planting area were identified through repeated visual interpretations of image information and spatial analyses conducted in GIS. Six vegetation indices were extracted from processed HJ-1A/1B satellite images to determine whether the winter wheat suffered from freezing injury and its degree of severity and recovery, using change vector analysis (CVA), the freeze injury representative vegetation index and the combination of the two methods, respectively. Accuracy of the freezing damage classification results was verified by determining the impact of freezing damage on yield and quantitative analysis. The CVA and the change of normalized difference vegetation index (ΔNDVI) monitoring results were different so a comprehensive analysis of the combination of CVA and ΔNDVI was performed. The area with serious freezing injury covered 0.9% of the total study area, followed by the area of no freezing injury (3.5%), moderate freezing injury (10.2%) and light freezing injury (85.4%). Of the moderate and serious freezing injury areas, 0.2% did not recover; 1.2% of the no freezing injury and light freezing injury areas showed optimal recovery, 15.6% of the light freezing injury and moderate freezing injury areas showed poor recovery, and the remaining areas exhibited general recovery.

A synthetic electron cyclotron emission (ECE) diagnostic is used to interpret ECE signals from preset plasma equilibrium profiles, including magnetic field, electron density, and electron temperature. According to the simulation results, the electron temperature ( T e) profile covering the harmonic overlap region can be obtained by receiving ECE signals at the high field side (HFS) of the HL-2M plasma. The third harmonic ECE at the low field side (LFS) cannot pass through the second harmonic resonance layer at the HFS unless the optical thickness ( τ) of the second harmonic becomes gray ( τ ≤ 2). In addition, the impact of the relativistic frequency down-shift has been evaluated and corrected. The measurable range of the HFS ECE has been calculated by scanning different parameters (electron density, temperature, and magnetic field). Higher plasma parameters allow a wider radial range of electron temperature measurements. The minimum inner measurable position can reach R = 120 cm (r/a = −0.89) when the product of core temperature ( T e0) and density ( n e0) is greater than 35 × 1019 keV m−3, which is extended by more than 30 cm inward compared with that of the LFS measurement. The HFS ECE will greatly improve the diagnostic ability of ECE systems on the HL-2M tokamak.

Pneumoconiosis is a type of occupational disease with extensive influence and serious harm. It is a systemic disease of diffuse pulmonary fibrosis caused by the inhalation of industrial dust into the lungs, and pneumoconiosis can continue to progress without further dust exposure, eventually leading to respiratory failure and death. With the wide application of new materials, new technologies and new crafting, the increasing demand for industrial materials, the survival of a large number of dust-exposed workers during the industrial boom in the 20th century, the incidence and cumulative number of pneumoconiosis cases continued to remain high, which caused a vast economic burden to the society. The pathogenesis of pneumoconiosis is relatively complex and known to be related to mechanical stimulation, oxidative stress, inflammation, immune response, and genetic predisposition. The immune system, as the defense of the body, plays an important role in the development of pneumoconiosis. This paper reviews the recent progress on the immunological pathogenesis of pneumoconiosis.尘肺病是职业病中影响广泛、危害严重的一类疾病，是由于生产性粉尘被吸入肺部进而蓄积所致的，以肺组织弥漫性纤维化为主的全身性疾病，且脱离了粉尘源，尘肺病仍可持续进展，最终导致呼吸衰竭，甚至死亡。随着新材料、新技术和新工艺的广泛应用，工业性材料需求的日益上涨，以及20世纪工业繁荣期大量接尘工人的存留，尘肺病的发病率及累计病例数仍持续呈高位，给社会造成了一定的经济负担。尘肺病的发病机制较为复杂，目前报道的机制与机械刺激、氧化应激、炎症、免疫反应和基因的多态性等相关。免疫系统作为保护机体的调控者，在尘肺病的发生发展中发挥重要作用，本文就尘肺病免疫发病机制的研究进展予以综述。.

ABSTRACT: In this paper, shale is used as the research rock sample and sandstone is used as the control rock sample. Different types of supersaturated solutions are used to form a special humidity environment to complete the control of the water saturation of the rock samples. The T2 distribution curves of the two rock samples under different relative humidity were obtained by nuclear magnetic resonance (NMR) technology. Comparing the T2 distribution curves of different relative humidity, it is found that the pores of shale are dominated by small pores, while the pores of sandstone are dominated by large pores. The quality analysis of water-saturated samples shows that the porosity of sandstone is about 12%, and the porosity of shale is about 4%. The relationship between relative humidity and water saturation is plotted, and it is found that the adsorption capacity of shale to water is much stronger than that of sandstone. By drawing the capillary force curve of the sample and fitting the Van-Genuchten (VG) model, the VG model parameters of the sample are obtained, the m of sandstone is 0.28, the α of sandstone is 34.5, and the m of shale is 0.38, the α of shale is 0.12. The above research on the evolution law of shale pore structure is of great significance to the further study of the law of its physical parameters. 1. INTRODUCTION Since 2000, the United States took the lead in launching the shale gas revolution due to major breakthroughs in horizontal drilling, hydraulic fracturing and other extraction technologies (Ciardo and Lecampion, 2021). According to prediction (Zhang et al., 2008), the global shale gas resource is 456 × 1012 m3, which is equivalent to the sum of the conventional natural gas, coalbed methane and tight gas in the world (471 × 1012 m3). Therefore, the commercial exploitation of shale gas is considered to be the most exciting and major achievement in the field of petroleum engineering in the past 100 years, which will change the global energy pattern greatly (Mi et al., 2010). In the Shale Gas Development Plan (2016-2020), the National Energy Administration of China pointed out that during the "Thirteenth Five-Year Plan" period, the production of shale gas will be 30 billion cubic meters by 2020, and the annual production volume will be 80-100 billion cubic meters by 2030. It can be seen that the development of shale gas exploitation also plays an important role in our country’s energy development.

Wound healing is a complex and critical process, which includes three stages: inflammation, proliferation, and remodeling. The epidermal cells are precisely regulated in this process. On one hand, keratinocytes around the wound edge migrate and proliferate to form a new basement membrane to cover the wound. On the other hand, the epidermal stem cells are activated with the proliferation and differentiation being enhanced, and the terminal differentiation and apoptosis being inhibited; and together with keratinocytes, epidermal stem cells promote the process of re-epithelialization under the regulation of various factors. In the epidermis, there is a group of resident T cell subsets, dendritic epidermal lymphocytes (DETCs) that play a key role in protecting the function of epidermal tissue. DETCs are activated after recognizing unknown antigens, the activated DETCs secret cytokines such as insulin-like growth factor Ⅰ, keratinocyte growth factor-1/2, granulocyte-macrophage colony stimulating factor, interferon-γ, and transforming growth factor-β, which promote epidermal homeostasis and re-epithelialization by regulating the dynamic balance among keratinocytes migration, proliferation, and apoptosis, and the differentiation of epidermal stem cells around the wound edge. This article discusses the biological characteristics of DETCs and their roles in the maintenance of epidermal homeostasis and wound healing.创面愈合是一个复杂而关键的过程，包括炎症、增殖和重塑3个阶段。表皮细胞在创面愈合中受到精密调控，一方面创缘周围的角质形成细胞通过迁移、增殖，形成新的基膜覆盖创面；另一方面表皮干细胞经过激活后，增殖分化被促进，终末分化、凋亡被抑制，角质形成细胞和表皮干细胞在各种因素调控下共同促进再上皮化进程。表皮组织中有一群对表皮组织功能维护有关键作用的T细胞亚群——树突状表皮T细胞（DETC）。DETC识别未知抗原后被激活，活化的DETC分泌胰岛素样生长因子Ⅰ、角质细胞生长因子1/2、粒细胞巨噬细胞集落刺激因子、γ干扰素、转化生长因子β等细胞因子，通过调节角质形成细胞迁移、增殖、凋亡之间的动态平衡以及创缘周围表皮干细胞的分化，促进表皮维持稳态和再上皮化。本文就DETC的生物特性、维持表皮稳态、在创面愈合中的作用几个方面展开讨论。.

It is challenging to increase the sensitivity of a hydrogen sensor operating at room temperature due to weak sorption and tiny mass of hydrogen. In this work, an ultrasonic sensor is presented for detecting hydrogen, which is composed of a 128° YX-LiNbO3 substrate and a reduced graphene oxide (RGO) sensitive layer with a platinum catalyzer. By optimizing the depositing parameters of RGO and platinum, a considerably high sensitivity is achieved at room temperature. A frequency shift of 308.9 kHz is obtained in 100 ppm hydrogen mixed with argon, and a frequency shift of 24.4 kHz is obtained in 1000 ppm hydrogen mixed in synthetic air. It is demonstrated that in addition to strong sorption of the sensitive layer, the coaction of mass load and conductivity variation is key to high sensitivity of the sensor. By establishing the original conductivity of the sensitive layer within the “conductivity window” for enhancing electrical response, we improve the sensitivity of the ultrasonic sensor, which is available for detecting hydrogen with an extremely low concentration of 5 ppm.

Objective To conduct bibliometric analysis of forensic genetics literatures published by Chinese mainland scholars in SCIE journals from 1989 to 2019, to show the research achievements of the past three decades and predict future research fields and directions. Methods Microsoft Office Excel 2019 was utilized to analyze the general situation, research institutions, authors, funds, author keywords, etc. of the literatures. The status of research in forensic genetics in Chinese mainland was visualized by PlotDB, Gephi 0.9.2 software and literature interpretation. Results During the last three decades, 1 126 forensic genetics literatures were published by scholars from Chinese mainland on SCIE journals, mostly articles. The quantity and quality of the literatures were both on the increase. The number of literatures published in1989—2019年SCIE收录的法医物证学文献计量学分析.目的 对Web of Science核心合集科学引文索引（Science Citation Index-Expanded，SCIE）数据库收录的1989—2019年中国大陆学者发表的法医物证学文献进行计量学分析，展现近30年来的研究成果，并预测未来的研究领域和方向。 方法 应用Microsoft Office Excel 2019软件对文献总体情况、研究机构、作者、基金资助、作者关键词等数据进行分析，通过PlotDB、Gephi 0.9.2软件和文献解读，对我国法医物证学领域研究现况进行数据可视化展示。 结果 近30年来，中国大陆学者发表的SCIE收录的法医物证学文献共1 126篇，以论文为主，数量和质量均呈上升趋势，发表于法医遗传学；文献计量学；共现分析；文献主题；短串联重复；单核苷酸多态性.

Reliability on 2.5D IC package is a big concern and challenge due to complicated packaging structure and high reliable requirement. Underfill failure such as delamination and cracking is one of common failure modes in 2.5D IC package when package is subjected to thermal aging condition. Underfill cracking occurs for 2.5D IC package with TSV interposer after high temperature storage (HTS) test. Failure mechanism is determined based on material characterization on underfill. Testing results show that underfill shrinkage increases with increasing HTS duration and interfacial strength of underfill/silicon decreases with increasing HTS duration. Thermal aging induced underfill shrinkage and interfacial strength degradation are main reasons resulting in failure. Finite element analysis (FEA) is conducted with modeling thermal induced shrinkage for 2.5D package under HTS condition. The predicted failure and location of underfill cracking is consistent with experimental observation when applying the developed new FEA model and material properties.

1例以宫内胎儿水肿为特征的患儿，新生儿期表现为间接胆红素增高为主的重度高胆红素血症、网织红细胞比例增高、重度贫血、肝脾肿大。基因测序结果显示存在SPTB基因移码变异，为c.5165_c.5166delTT，为新发变异，确诊为遗传性球形红细胞增多症。以非免疫性胎儿水肿为特征的遗传性球形红细胞增多症少见，对于临床高度怀疑而常规辅助检查不支持的新生儿遗传性球形红细胞增多症，基因检测可协助确诊。.

Growing evidence has revealed that circular RNAs (circRNAs) play important roles in the development of cancers, including colorectal cancer (CRC). In this study, we mainly focused on the expression of circ_0056618 and potential functions of circ_0056618 in CRC patients.RT-PCR was performed to detect circ_0056618 and miR-206 expressions in CRC tissues and adjacent non-tumor tissues. Correlation analysis was used to analyze the correlation between circ_0056618 and miR-206. Kaplan-Meier method was conducted to analyze the overall survival (OS) for CRC patients. Moreover, CCK-8 assay was used to measure cell proliferation ability and transwell assay was performed to detect cell migration ability. Besides, tube formation assay was performed to measure cell angiogenesis capacity. Western blot (WB) was performed to measure protein levels of tissues samples and CRC cell lines. Notably, the Luciferase reporter assay was performed to prove the binding sites in circ_0056618 with miR-206, miR-206 with CXCR4 and VEGF-A.We found that circ_0056618 was elevated in CRC tumor tissues and CRC cell lines, which was related to poor diagnosis for CRC patients. MiR-206 was reduced in CRC tissues, which was negatively related with circ_0056618. Protein levels of CXCR4 and VEGF-A were elevated in CRC tumor tissues, which were negatively related with miR-206. Circ_0056618 inhibition inhibited proliferation, angiogenesis and migration of HT29 cells, and repressed protein levels of Cyclin D1, VEGF-A and N-cadherin and increased E-cadherin. Notably, Luciferase reporter assay indicated that circ_0056618 could sponge with miR-206, which could directly target at CXCR4 and VEGF-A. Finally, we proved a pathway that circ_0056618 promoted cell proliferation, migration and angiogenesis through sponging with miR-206 and removing the repressing effects of miR-206, thereby upregulating CXCR4 and VEGF-A in CRC.Above all, this study revealed that circ_0056618 was increased in CRC tissues, which was related with the poor OS of CRC patients. We found that circ_0056618 could promote cell proliferation, migration and angiogenesis through sponging with miR-206 and upregulating CXCR4 and VEGF-A in CRC, which might provide a novel potential therapeutic target for treating CRC.

Coronavirus disease 2019 (COVID-19) has seriously affected the safety of patients and social stability. Some COVID-19 patients in the later stage of disease may develop into acute respiratory distress syndrome or even multiple organ failure. However, one of the most important mechanisms underlying the deterioration of disease is cytokine storm. At present, some therapies such as interleukin-6 antibody blocker, stem cell therapy, and transfusion of convalescent plasma have been applied to counteract the cytokine storm with some progresses being achieved. This article reviews the influences of cytokine storm syndrome on the COVID-19 and the corresponding immunotherapies to resist cytokine storm.新型冠状病毒肺炎(COVID-19)已严重影响了患者的生命安全和社会稳定。部分COVID-19患者在疾病后期可发展为急性呼吸窘迫综合征甚至多器官功能衰竭，而导致这一病情转变潜在的重要机制就是细胞因子风暴的产生。目前，白细胞介素6抗体阻断剂、干细胞疗法和回输康复患者血清等方法缓解细胞因子风暴已取得一定进展。本文就细胞因子风暴对COVID-19的影响及抵抗细胞因子风暴的免疫治疗方法进行综述。.

In China, the invasive American serpentive leafminer, Liriomyza trifolii (Burgess), was first detected in Guangdong province in 2005. Within only a few years of its discovery, its range had expanded rapidly to another 11 provinces and caused economic damage to a wide range of agricultural crops. L. trifolii has displaced the previously established exotic species L. sativae Blanchard to become the dominant species on some major horticultural crops across Hainan Island. Differential insecticide susceptibilities and local specific cropping systems might be major factors driving the ongoing displacement of L. sativae by L. trifolii. Further research should focus on monitoring established species to collect detailed data to enhance overall understanding of biology and ecology of invasion by L. trifolii. Urgent action is needed to improve management programs for this widespread invasive insect pest.

The aim is to determine the efficacy and specific mechanism of microRNA-543-5p (miR-543-5p) on spinal cord injury (SCI).The model of spinal cord injury was established in 6-week-old rats. Firstly, quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was used to detect the changes of miR-543-5p in the spinal cord of rats in each group after spinal cord injury. Next, we observed the alterations in nuclear factor-kappa B (NF-κB) RNA level after injection of miR-543-5p. In addition, the enzyme-linked immunosorbent assay (ELISA) was used to detect the expression of the inflammatory cytokines, and we used Western blotting to detect the protein associated with nerve regeneration at the protein levels. Finally, the Basso-Beattie-Bresnahan (BBB) rating scale was utilized to measure the recovery of hindlimbs function in rats.After spinal cord injury, the RNA expression of miR-543-5p in the rat spinal cord was decreased, and the RNA level of NF-κB was found to be decreased after the artificial injection of miR-543-5p. In the inflammatory expression, we found that the expression of various inflammatory mediators was also downregulated. However, the expression of nerve regeneration related factors was significantly upregulated, and it was observed that the evaluated score of the miR-543-5p group was higher than that of the SCI group within 1 month.MiR-543-5p inhibited NF-κB pathway and reduced the inflammatory factors, and ameliorated nerve regeneration, which ultimately promoted hindlimbs locomotor function.

The development of eco-friendly chromium-free refractory products has been attracting more and more attention for environmental protection reasons. Refractories from the MgO-Al2O3-SnO2 system were selected as chrome-free alternatives. Novel spinel-based castables with SnO2 have the potential to be used in copper smelting. The effect of SnO2 addition up to 10 mass-% on the properties of spinel-based castables was investigated. Phase composition, microstructure, physical and mechanical properties as well as corrosion resistance of the refractories were characterized. The results showed that spinel-based castables with 10 mass-% SnO2 after firing at 1350 °C presented the best comprehensive performance due to lower porosity and higher strength.

Ingestion of magnetic foreign bodies is an increasing problem in the pediatric emergency in recent years.The majority of these injuries are ingestions involving the gastrointestinal tract, stomach, esophagus etc.Ingestion of multiple magnets has a high risk of bowel injury such as perforation or fistula. It needs us to pay attention to early assessment and appropriate intervention. Magnetic foreign bodies are usually from toys, a small part from medical instruments or accessories etc. It is infrequently reported that magnetic foreign body lodge in the hypopharynx, because the shape of it is spherical, button and a glaze surface. Now we have a case of magnetic foreign body involving hypopharynx.

Metallic nanoparticles with plasmonic properties have extensive potential applications in biodiagnostics and sensing, bioimaging and solar cells, but a comprehensive theoretical and experimental investigation of the phenomenon is far from being complete. In this manuscript, about 30, 40 and 50 nm Au nanoparticles were synthesised by Frens method, and Au/SiO2 nanoparticles were obtained by a modified Stober method; the thickness of SiO2 layer were adjusted from 15 to 45 nm. The effect of Au size and SiO2 dielectric layer thickness on the plasmonic properties of Au/SiO2 nanoparticles were numerically simulated by 3D comsol and were experimentally studied by UV-vis absorption spectra. UV-vis absorption spectra showed that the increase in Au particle size or SiO2 thickness resulted in a red shift of the surface plasmon resonance absorption peak of Au/SiO2 nanoparticles, which is consistent with the simulation results by 3D comsol. Thicker SiO2 layer and smaller Au nanoparticles led to the decrease of ...

When the gait feature is recognized, it will be hard to meet the real-time need due to the complexity and long calculated time of the recognition algorithm. Under this circumstance, a novel sparse representation based human gait recognition method is put forth which is based on. First of all, human silhouette is established and gait period is calculated. Next, we adopt Shifting Energy Image (SEI) as the feature of image and then extract Gabor Wavelet and Local Binary Pattern features. Finally, gait feature will be classified and recognized by using sparse representation. CASIA B gait database will be used in the experiment with a view of 90 degrees. The result witnesses that this method has higher recognition rate and can meet the needs of real-time.

To investigate the impact of previous cystectomy for ovary benign cyst on ovarian reserve and pregnancy outcome in in vitro fertilization/intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET) cycles.Totally 622 infertility patients were retrospectively investigated who underwent first IVF/ICSI-ET cycle in Reproductive Hospital Affiliated to Shandong University from January 2013 to June 2014. There were 153 cases who had been removed ovarian cyst by cystectomy surgeries recruited as study group, in which 44 cases of ovarian endometriosis cyst, 35 cases of benign ovarian teratomas, 67 cases of simple ovarian cyst and 7 cases of ovarian mucinous cystadenoma. In contrast, 469 infertility patients with tubal-factor infertility or male factor were included as control group. The age-matched women in the control group had no ovarian surgery previously. The indicators of ovarian reserve and pregnancy outcome were analyzed between two groups. The influence of different types of ovarian cysts on ovarian reserve and pregnancy outcome in IVF/ICSI-ET cycles were also studied, ovarian endometriosis cyst was studied as Group A, and Group B consisted of benign ovarian teratomas, simple ovarian cyst and mucinous cystadenoma.(1) The significantly lower serum antimullerian hormone (AMH) level (median: 1.92 versus 2.90 mg/L), antral follicle count (AFC; median: 12.0 versus 13.0), retrieved oocytes (12±5 versus 13±6) and the number of embryo cryopreserved (median: 1.0 versus 3.0) were found in study group compared with control group (all P0.05). There was no statistical difference between two group for the following parameters, such as basal FSH level, the total dosage of gonadotropin duration and the total dosage of gonadotropin (all P0.05). A better clinical pregnancy rate was achieved in control group (61.6%, 241/391) than that in study group (61.4%, 81/132), but no significant difference was existed (P=0.96). (2) Compared to Group B, Group A had fewer AFC, lower serum AMH level, retrieved oocytes and the number of embryo cryopreserved (11±4 versus 13±5; 1.65 versus 2.15 mg/L; 9±4 versus 13±5; 0 versus 2.0; all P0.01). There was a lower clinical pregnancy rate in Group A than that in Group B [50.0% (19/38) versus 66.0% (62/94)], accompanying with higher abortion rate [3/19 versus 9.7% (6/62)], but no differences were observed (all P0.05).Ovarian reserve declines after the cystectomy for ovarian benign cysts and the cystectomy has a negative impact on IVF/ICSI-ET cycle, resulting in a decrease of the number of retrieved oocytes and the number of embryo cryopreserved, but do not influence clinical pregnancy outcome. Ovarian reserve is impaired more seriously by cystectomy for ovarian endometriosis cyst than other ovarian benign cyst.

A compact ultra-wideband (UWB) bandpass filter (BPF) with a narrow notched band based on ridged waveguide is presented. Capacitive loading stub structure is introduced to reject the undesired wireless local-area network (WLAN) radio signals. By simply adjusting the height of the capacitive loading post, the centre frequencies of the notched band can be changed from 5.16 to 6.2GHz, while the bandpass is nearly not affected. The UWB BPF has been simulated, fabricated and measured, with good agreement between the simulated and measured results. The measured insertion loss of the UWB BPF is less than 0.7 dB throughout the pass band of 3.05 to 10.9GHz, the variation of group delay less than 0.20 ns in this band except for the notched band. The notched band of the BPF centred at 5.2GHz has 10dB fractional bandwidth of about 3.7%.

There is a rapid transition in the semiconductor packaging industry of devices moving toward 40/45-nm extreme low k (ELK) from the development phase into mainstream semiconductor assembly manufacturing. The drive to achieve adoption without major changes to process and equipment infrastructure while meeting the superior yield necessary is high. The main goal of this paper is to share learning's and provide solutions for integration and qualifications of 40/45-nm ELK devices into flip-chip (FC) and wire-bond (WB) package technology. The scope of this paper covers the fine-pitch ball grid array for the WB packages and FC chip-scale package for the FC Devices. The main challenge and focus point for WB 45/40-nm interconnects is on the first bond process. This paper will share some detailed analysis on the following. 1) Characterization for 45 nm ELK ultrafine-pitch. 2) Key factors for good Au ball bond integrity. 3) Recommendations for achieving the required levels of reliability for 45-nm Cu ELK. The challenge of FC Technology today has been changing at a faster rate and more and more adoption has been made from the conventional eutectic solder bumps or high lead solder bumps toward the lead free solder bump mainly due to the Green initiatives. This paper will share analysis on the following areas. 1) Thermo-mechanical simulation on key input factors and its correlation to actual evaluations. 2) Integration of Pb Free ELK bumps with 40-nm ELK technology are various critical processes. 3) Moldable underfill technology for Pb Free + ELK devices. In addition, critical process control is also required at the wafer level process of wafer thinning and dicing, including the need of Laser Grooving will also be covered.

In this article, a supercritical CO2-based solar Rankine cycle system (SRCS) with a novel-concept thermally driven pump is studied. The thermally driven pump is a refrigerant-circulating pump composed of two expansion tanks and having merits of low power consumption and high reliability in comparison with conventional mechanical pump. The application of the present thermally driven pump in the supercritical CO2-based SRCS shows that an oscillatory flow is realized in the system and the system thermal efficiency is enhanced compared to the SRCS using the mechanical feed pump.

Phase change materials (PCM) have been extensively scrutinized for their widely application in thermal energy storage (TES). Paraffin was considered to be one of the most prospective PCMs with perfect properties. However, lower thermal conductivity hinders the further application. In this letter, we experimentally investigate the thermal conductivity and energy storage of composites consisting of paraffin and micron-size graphite flakes (MSGFs). The results strongly suggested that the thermal conductivity enhances enormously with increasing the mass fraction of the MSGFs. The formation of heat flow network is the key factor for high thermal conductivity in this case. Meanwhile, compared to that of the thermal conductivity, the latent heat capacity, the melting temperature, and the freezing temperature of the composites present negligible change with increasing the concentration of the MSGFs. The paraffin-based composites have great potential for energy storage application with optimal fraction of the MSGFs.

In this work, tensile creep tests for Sn-1.0Ag-0.5Cu-0.02Ni solder have been conducted at various temperatures and stress levels to determine its creep properties. The effects of stress level and temperature on creep strain rate were investigated. Creep constitutive models (such as the simple power-law model, hyperbolic sine model, double power-law model, and exponential model) have been reviewed, and the material constants of each model have been determined based on experimental results. The stress exponent and creep activation energy have been studied and compared with other researchers’ results. These four creep constitutive models established in this paper were then implemented into a user-defined subroutine in the ANSYS™ finite-element analysis software to investigate the creep behavior of Sn-1.0Ag-0.5Cu-0.02Ni solder joints of thin fine-pitch ball grid array (TFBGA) packages for the purpose of model comparison and application. Similar simulation results of creep strain and creep strain energy density were achieved when using the different creep constitutive models, indicating that the creep models are consistent and accurate.