Back Interface and Absorber Bulk Deep-Level Trap Optimization Enables Highly Efficient Flexible Antimony Triselenide Solar Cell.

The unique 1D crystal structure of Antimony Triselenide (Sb2Se3) offers notable potential for use in flexible, lightweight devices due to its excellent bending characteristics. However, fabricating high-efficiency flexible Sb2Se3 solar cells is challenging, primarily due to the suboptimal contact interface between the embedded Sb2Se3 layer and the molybdenum back-contact, compounded by complex intrinsic defects. This study introduces a novel Molybdenum Trioxide (MoO3) interlayer to address the back contact interface issues in flexible Sb2Se3 devices. Further investigations indicate that incorporating a MoO3 interlayer not only enhances the crystalline quality but also promotes a favorable [hk1] growth orientation in the Sb2Se3 absorber layer. It also reduces the barrier height at the back contact interface and effectively passivates harmful defects. As a result, the flexible Sb2Se3 solar cell, featuring a Mo-foil/Mo/MoO3/Sb2Se3/CdS/ITO/Ag substrate structure, demonstrates exceptional flexibility and durability, enduring large bending radii and multiple bending cycles while achieving an impressive efficiency of 8.23%. This research offers a straightforward approach to enhancing the performance of flexible Sb2Se3 devices, thereby expanding their application scope in the field of photovoltaics.

Thermodynamic Study on Hydrogen Reduction of Germanium Tetrachloride to Germanium.

This study elucidates the thermodynamic reaction mechanism of the GeCl4 hydrogen reduction process for Ge preparation. Five independent reactions in the Ge-Cl-H ternary system were identified, utilizing the phase law, mass conservation principles, and thermodynamic data, with H2 as the reducing agent. Additionally, the effects of the temperature, feed ratio, and pressure on the germanium deposition rate during the GeCl4 hydrogen reduction process were investigated, guided by these five reactions. The results indicate that, with fixed temperature and pressure, a higher feed ratio (nH2/nGeCl4) leads to an increased germanium deposition rate. Conversely, with a constant feed ratio, increased pressure results in a lower deposition rate at low temperatures. The optimal operating conditions for germanium preparation via the hydrogen reduction of GeCl4 were determined: the temperature was 450 °C, the feed ratio was 20, the pressure was 0.1 MPa, and the deposition rate of the germanium was 36.12% under this condition.

Microbial communities and functions changed in rhizosphere soil of Pinus massoniana provenances with different carbon storage.

Introduction: The average carbon storage of Pinus massoniana is much higher than the average carbon storage of Chinese forests, an important carbon sink tree species in subtropical regions of China. However, there are few studies on the differences in rhizosphere microorganisms of P. massoniana with different carbon storages. Methods: To clarify the relationships between plant carbon storage level, environmental parameters and microbial community structure, we identified three carbon storage levels from different P. massoniana provenances and collected rhizosphere soil samples. We determined chemical properties of soil, extracellular enzyme activity, and microbial community structures at different carbon storage levels and examined how soil factors affect rhizosphere microorganisms under different carbon storage levels. Results: The results revealed that soil organic carbon (SOC), nitrate nitrogen (NO3--N), ammonium nitrogen (NH4+-N) contents all increased with increasing carbon storage levels, while pH decreased accordingly. In contrast, the available phosphorus (AP) content did not change significantly. The soil AP content was within the range of 0.91 ~ 1.04 mg/kg. The microbial community structure of P. massoniana changed with different carbon storage, with Acidobacteria (44.27%), Proteobacteria (32.57%), and Actinobacteria (13.43%) being the dominant bacterial phyla and Basidiomycota (73.36%) and Ascomycota (24.64%) being the dominant fungal phyla across the three carbon storage levels. Soil fungi were more responsive to carbon storage than bacteria in P. massoniana. C/N, NH4+-N, NO3--N, and SOC were the main drivers (p < 0.05) of changes in rhizosphere microbial communities. Discussion: The results revealed that in the rhizosphere there were significant differences in soil carbon cycle and microorganism nutrient preferences at different carbon storages of P. massoniana provenance, which were significantly related to the changes in rhizosphere microbial community structure. Jiangxi Anyuan (AY) provenance is more suitable for the construction of high carbon storage plantation.

Effect of Template-Mediated Alumina Nanoparticle Morphology on Sapphire Wafer Production via Heat Exchange Method.

The sapphire crystal, the most commonly used LED substrate material, has excellent optical and chemical properties and has rapidly developed in recent years. However, the challenge of growing large-size sapphire crystals remains. This paper presents a novel approach using alumina nanoparticles synthesized with abietic acid as a template to enhance sapphire growth via the heat exchange method. This study explores the effects of temperature, time, and template amount on the structure and morphology of the synthesized alumina nanoparticles. The results show that the morphology of the raw material, particularly spherical alumina nanoparticles, positively affects the quality and yield stability of sapphire products. Furthermore, the light output power of GaN-based LED chips made with the experimentally fabricated sapphire substrate increased from 3.47 W/µm2 to 3.71 W/µm2, a 6.9% increase compared to commercially available sapphire substrates. This research highlights the potential of using abietic acid as a template for alumina nanoparticle synthesis and their application in sapphire growth for LED production.

The Morphologically Controlled Synthesis and Application of Mesoporous Alumina Spheres.

The control of alumina morphology is crucial yet challenging for its various applications. Unfortunately, traditional methods for preparing alumina particles suffer from several limitations such as irregular morphology, poor dispersibility, and restricted application areas. In this study, we develop a novel method for preparing spherical mesoporous alumina using chitin and Pluronic P123 as mixed templates. The effects of reaction temperature, time, and the addition of mixed templates on the phase structure, micromorphology, and optical absorption properties of the samples were investigated. The experimental results indicate that lower temperature and shorter reaction time facilitated the formation of spherical mesoporous alumina with excellent CO2 adsorption capacity. The periodic density functional theory (DFT) calculations demonstrate that both the (110) and (100) surfaces of γ-Al2O3 can strongly adsorb CO2. The difference in the amount of CO2 adsorbed by Al2O3 is mainly due to the different surface areas, which give different numbers of exposed active sites. This approach introduces a novel strategy for utilizing biological compounds to synthesize spherical alumina and greatly enhances mesoporous alumina's application efficiency in adsorption fields. Moreover, this study explored the electrochemical performance of the synthesized product using cyclic voltammetry, and improved loading of electrocatalysts and enhanced electrocatalytic activity were discovered.

Human placental exosomes induce maternal systemic immune tolerance by reprogramming circulating monocytes.

BACKGROUND: The maternal immune system needs to tolerate the semi-allogeneic fetus in pregnancy. The adaptation occurs locally at the maternal-fetal interface as well as systemically through the maternal circulation. Failure to tolerate the paternal antigens may result in pregnancy complications, such as pregnancy loss and pre-eclampsia. However, the mechanism that regulates maternal immune tolerance, especially at the systemic level, is still an enigma. Here we report that the first-trimester placenta-derived exosomes (pEXOs) contribute to maternal immune tolerance by reprogramming the circulating monocytes. RESULTS: pEXOs predominantly target monocytes and pEXO-educated monocytes exhibit an immunosuppressive phenotype as demonstrated by reduced expression of marker genes for monocyte activation, T-cell activation and antigen-process/presentation at the transcriptomic level. They also have a greater propensity towards M2 polarization when compared to the monocytes without pEXO treatment. The inclusion of pEXOs in a monocyte-T-cell coculture model significantly reduces proliferation of the T helper cells and cytotoxic T cells and elevates the expansion of regulatory T cells. By integrating the microRNAome of pEXO and the transcriptomes of pEXO-educated monocytes as well as various immune cell functional assays, we demonstrate that the pEXO-derived microRNA miR-29a-3p promotes the expression of programmed cell death ligand-1, a well-known surface receptor that suppresses the adaptive immune system, by down-regulation of phosphatase and tensin homolog in monocytes. CONCLUSIONS: This is the first report to show how human pEXO directly regulates monocyte functions and its molecular mechanism during early pregnancy. The results uncover the importance of pEXO in regulating the maternal systemic immune response during early pregnancy by reprogramming circulating monocytes. The study provides the basis for understanding the regulation of maternal immune tolerance to the fetal allograft.

Experimental and Simulation Research on the Preparation of Carbon Nano-Materials by Chemical Vapor Deposition.

Carbon nano-materials have been widely used in many fields due to their electron transport, mechanics, and gas adsorption properties. This paper introduces the structure and properties of carbon nano-materials the preparation of carbon nano-materials by chemical vapor deposition method (CVD)-which is one of the most common preparation methods-and reaction simulation. A major factor affecting the material structure is its preparation link. Different preparation methods or different conditions will have a great impact on the structure and properties of the material (mechanical properties, electrical properties, magnetism, etc.). The main influencing factors (precursor, substrate, and catalyst) of carbon nano-materials prepared by CVD are summarized. Through simulation, the reaction can be optimized and the growth mode of substances can be controlled. Currently, numerical simulations of the CVD process can be utilized in two ways: changing the CVD reactor structure and observing CVD chemical reactions. Therefore, the development and research status of computational fluid dynamics (CFD) for CVD are summarized, as is the potential of combining experimental studies and numerical simulations to achieve and optimize controllable carbon nano-materials growth.

[Ultrasonographic and clinical features of common testicular germ cell tumors in children].

OBJECTIVE: To study the ultrasonographic manifestations and clinical features of common pediatric testicular germ cell tumors (TGCT) in children. METHODS: We retrospectively analyzed the laboratory, ultrasonographic and clinical data on 92 children with TGCT diagnosed in Shanghai Children's Hospital from March 2013 to January 2019, and investigated the values of the serum alpha-fetoprotein (AFP) level and maximum diameter of tumors in the diagnosis of benign and malignant tumors using the ROC curve. RESULTS: Of the 92 cases of pediatric TGCT, 64 (69.6%) were pathologically confirmed as benign tumors, including 40 cases of teratoma (62.5%), 18 cases of epidermoid cyst (28.1%) and 6 cases of dermoid cyst (9.4%), and the other 28 (30.4%) as malignant neoplasms, including 26 cases of yolk sac tumor (YST, 92.9%) and 2 cases of mixed germ cell tumor (MGCT, 7.1%). Ultrasonography showed that 62.5% of the teratomas were cystic-solid mixed (25/40) and 32.5% solid masses (12/40), that 33.3% of the epidermoid cysts exhibited a typical sign of "onion ring" (6/18) and 22.2% that of capsular calcification (4/18), and that 42.3% of the YSTs displayed isoechoic (11/26), 30.9% hypoechoic (8/26) solid masses without calcium and 26.9% cystic anechoic lesions (7/26). Color Doppler blood flow imaging manifested abundant blood flow signals in most of the YSTs (25/26, 96.2%) but none in either the epidermoid or the dermoid cysts. The area under the ROC curve (AUC) of the serum AFP value was 0.985, with an optimal cutoff value of 124.2 ng/ml, and the sensitivity and specificity of AFP in the diagnosis of benign and malignant tumors were 92.9% and 93.7%, respectively. The AUC of the maximum diameter of the tumors was 0.796, with an optimal cutoff value of 2.7 cm, and the sensitivity and specificity of the maximum diameter of the tumors in the diagnosis of benign and malignant neoplasms were 57.1% and 93.7%, respectively. CONCLUSIONS: Ultrasonographic images have different characteristic manifestations for different pathological types of pediatric TGCT. Pediatric TGCT has a good prognosis and radical orchiectomy should be considered for the treatment of the tumors with serum AFP ≥ 124.2 ng/ml and a diameter ≥ 2.7 cm.

An Efficient Implementation of Fixed Failure-Rate Ratio Test for GNSS Ambiguity Resolution.

Ambiguity Resolution (AR) plays a vital role in precise GNSS positioning. Correctly-fixed integer ambiguities can significantly improve the positioning solution, while incorrectly-fixed integer ambiguities can bring large positioning errors and, therefore, should be avoided. The ratio test is an extensively used test to validate the fixed integer ambiguities. To choose proper critical values of the ratio test, the Fixed Failure-rate Ratio Test (FFRT) has been proposed, which generates critical values according to user-defined tolerable failure rates. This contribution provides easy-to-implement fitting functions to calculate the critical values. With a massive Monte Carlo simulation, the functions for many different tolerable failure rates are provided, which enriches the choices of critical values for users. Moreover, the fitting functions for the fix rate are also provided, which for the first time allows users to evaluate the conditional success rate, i.e., the success rate once the integer candidates are accepted by FFRT. The superiority of FFRT over the traditional ratio test regarding controlling the failure rate and preventing unnecessary false alarms is shown by a simulation and a real data experiment. In the real data experiment with a baseline of 182.7 km, FFRT achieved much higher fix rates (up to 30% higher) and the same level of positioning accuracy from fixed solutions as compared to the traditional critical value.