Chlorine-Substituent Regulation in Dopant-Free Small-Molecule Hole-Transport Materials Improves the Effi ciency and Stability of Inverted Perovskite Solar Cells

Although doped hole-transport materials(HTMs)off er an effi ciency benefi t for perovskite solar cells(PSCs),they inevi-tably diminish the stability.Here,we describe the use of various chlorinated small molecules,specifi cally fl uorenone-triphenylamine(FO-TPA)-x-Cl[x=para,meta,and ortho(p,m,and o)],with diff erent chlorine-substituent positions,as dopant-free HTMs for PSCs.These chlorinated molecules feature a symmetrical donor-acceptor-donor structure and ideal intramolecular charge transfer properties,allowing for self-doping and the establishment of built-in potentials for improving charge extraction.Highly effi cient hole-transfer interfaces are constructed between perovskites and these HTMs by strategi-cally modifying the chlorine substitution.Thus,the chlorinated HTM-derived inverted PSCs exhibited superior effi ciencies and air stabilities.Importantly,the dopant-free HTM FO-TPA-o-Cl not only attains a power conversion effi ciency of 20.82% but also demonstrates exceptional stability,retaining 93.8%of its initial effi ciency even after a 30-day aging test conducted under ambient air conditions in PSCs without encapsulation.These fi ndings underscore the critical role of chlorine-substituent regulation in HTMs in ensuring the formation and maintenance of effi cient and stable PSCs.

Accurate machine learning models based on small dataset of energetic materials through spatial matrix featurization methods

A large database is desired for machine learning(ML) technology to make accurate predictions of materials physicochemical properties based on their molecular structure.When a large database is not available,the development of proper featurization method based on physicochemical nature of target proprieties can improve the predictive power of ML models with a smaller database.In this work,we show that two new featurization methods,volume occupation spatial matrix and heat contribution spatial matrix,can improve the accuracy in predicting energetic materials' crystal density(ρ_(crystal)) and solid phase enthalpy of formation(H_(f,solid)) using a database containing 451 energetic molecules.Their mean absolute errors are reduced from 0.048 g/cm~3 and 24.67 kcal/mol to 0.035 g/cm~3 and 9.66 kcal/mol,respectively.By leave-one-out-cross-validation,the newly developed ML models can be used to determine the performance of most kinds of energetic materials except cubanes.Our ML models are applied to predict ρ_(crystal) and H_(f,solid) of CHON-based molecules of the 150 million sized PubChem database,and screened out 56 candidates with competitive detonation performance and reasonable chemical structures.With further improvement in future,spatial matrices have the potential of becoming multifunctional ML simulation tools that could provide even better predictions in wider fields of materials science.

Application of prolonging small feeding volumes early in life to prevent of necrotizing enterocolitis in very low birth weight preterm infants

Objective:To study the effects of prolonging small feeding volumes early in life on the incidence of necrotizing enterocolitis(NEC)in very low birth weight(VLBW)preterm infants.Methods:A total of 128 VLBW infants who could not be breastfed were assigned into the experimental group(63 cases)and the control group(65 cases)using a random number table.The experiment group was fed 12 mL/(kg·d)on day 1 which was increased to 24 mL/(kg·d)for the first 10 study days.The control group was fed 12 mL/(kg·d)for the first 14e48 hours.Then,the feeding volume increased by 24-36 mL/(kg·d)up to 140e160 mL/(kg·d)and maintained until the 10th day after birth.The incidence of feeding intolerance and NEC,duration of hospitalization,time to full enteral feedings,incidence of intrahepatic cholestasis,and the levels of gastrin and motilin in serum were assessed.Results:The incidence of feeding intolerance was significantly lower in the experimental group compared with the control group(15.87% vs.33.84%).There was a significant reduction in the incidence of NEC between the experimental and control groups(7.9% vs.16% in the control group).Conclusion:A protocol that prolongs small feeding volumes early in life can reduce the incidence and severity of NEC,but still warrants further study.

Study on the Application of Small Woodblock Turf in Garden Landscape

The development status of small woodblock turf in China and abroad was introduced in this study, the significance and advantage of such a technology as well as its application in garden landscape were also summarized, and finally advices to further develop small woodblock turf were put forward.

A two-scale method for identifying mechanical parameters of composite materials with periodic configuration

In this paper, a two-scale method （TSM） is presented for identifying the mechanics parameters such as stiffness and strength of composite materials with small periodic configuration. Firstly, a formulation is briefly given for two-scale analysis （TSA） of the composite materials. And then a two-scale computation formulation of strains and stresses is developed by displacement solution with orthotropic material coefficients for three kinds of such composites structures, i.e., the tension column with a square cross section, the bending cantilever with a rectangular cross section and the torsion column with a circle cross section. The strength formulas for the three kinds of structures are derived and the TSM procedure is discussed. Finally the numerical results of stiffness and strength are presented and compared with experimental data. It shows that the TSM method in this paper is feasible and valid for predicting both the stiffness and the strength of the composite materials with periodic configuration.

A Plasmonic Mass Spectrometry Approach for Detection of Small Nutrients and Toxins

Nutriology relies on advanced analytical tools to study the molecular compositions of food and provide key information on sample quality/safety. Small nutrients detection is challenging due to the high diversity and broad dynamic range of molecules in food samples, and a further issue is to track low abundance toxins. Herein, we developed a novel plasmonic matrix-assisted laser desorption/ionization mass spectrometry(MALDI MS)approach to detect small nutrients and toxins in complex biological emulsion samples. Silver nanoshells(SiO_2@-Ag) with optimized structures were used as matrices andachieved direct analysis of ~ 6 n L of human breast milk without any enrichment or separation. We performed identification and quantitation of small nutrients and toxins with limit-of-detection down to 0.4 pmol(for melamine) and reaction time shortened to minutes, which is superior to the conventional biochemical method currently in use. The developed approach contributes to the near-future application of MALDI MS in a broad field and personalized design of plasmonic materials for real-case bio-analysis.

High Efficiency Axial Deep Creep-Feed Grinding Machining Technology of Engineering Ceramics Materials

Axial deep creep-feed grinding machining technology is a high efficiency process method of engineering ceramics materials, which is an original method to process the cylindrical ceramics materials or hole along its axis. The analysis of axial force and edge fracture proved the cutting thickness and feed rate could be more than 5-10 mm and 200 mm/min respectively in once process, and realized high efficiency, low-cost process of engineering ceramics materials. Compared with high speed-deep grinding machining, this method is also a high efficiency machining technology of engineering ceramics materials as well as with low cost. In addition, removal mechanism analyses showed that both median/radial cracks and lateral cracks appeared in the part to be removed, and the processed part is seldom destroyed, only by adjusting the axial force to control the length of transverse cracks.

Evaluation of the Immunoregulatory Capacities of Feed Microbial Materials in Porcine Intestinal Immune and Epithelial Cells

The establishment of drug-free feeding systems has been required for secure and healthy livestock production. Although functional feed materials containing microorganisms as alternatives to enhance intestinal immunity are expected to be beneficial for reducing diarrhoea caused by pathogens in weaned piglets, the effects of such materials on porcine intestinal cells have not been investigated in detail. Therefore, this work evaluated the immunoregulatory functions of microbial feed materials in porcine intestinal immune and epithelial cells. Porcine immune cells isolated from Peyer’s patches and mesenteric lymph nodes were stimulated with six different feed materials containing microorganisms, and evaluated for lymphocyte mitogenicity and cytokine inductions. In addition, porcine intestinal epithelial cells were stimulated with the materials before treatment with heat-killed enterotoxigenic Escherichia coli (ETEC), and analyzed for the proinflammatory cytokine expressions. The material containing Bifidobacterium thermophilum significantly augmented lymphocytes’ mitogenicity and also induced a high expression of IL-2, IL-6 and IFN-γ in immune cells, and inhibited ETEC-induced overexpression of IL-6 and IL-8 via regulation of Toll-like receptor signaling. These results suggest that this feed material stimulates intestinal epithelial and immune cells to exert immunoregulation, suggesting that this feed is expected to contribute to promoting the health of piglets without using antimicrobial feed materials.

SEPARATION OF MATERIALS IN SWIRL SHAFT PREHEATER

On the basis of theoretical analysis and cold model test, the material motion locus and the particle size which can be separated in the swirl shaft preheater was stud-ied. A new calculation method for separation efficiency based on the meterial size distribution curve of charge and dis-charge stock from the shaft is discussed in this paper. The ex-perimental results show the material separation is due to in-teraction of both the centrifugation and the gravity. When the inlet gas velocity is a constant, the separation efficiency will be raised as the load of batch feeding inreases. If the load of batch feeding is a constant, the separation efficiency will be decreased together with the elevation of the inlet gas. The loss of shaft resistence is increased when the separation effi-ciency is raised. In our experiment the suitable separation ef-ficiency of the shaft is about 70 percent.

Monolithic Catalysts with Low Noble-Metal Content for Exhaust Purification of Small Gasoline Engines

A series of low noble-metal coment monolithic catalysts for exhaust purification of small gasoline engines was investigated, and it was found that the Pt/Rh-OSM/Al2O3 （where OSM was oxygen storage material） catalyst with Ce0.5Zr0.5-MnOx（3%MnOx） OSM held low light-off temperature for CO, HC, and NO; quite wide three-way window, and outstanding thermal stability. The catalyst could efficiently comrol exhaust emission of small gasoline engines.

One-Pot Synthesis of Tetraarylpyrrolo[3,2-b]pyrrole Dopant-Free Hole-Transport Materials for Inverted Perovskite Solar Cells

Four organic smallmolecule hole transport materials(D41, D42,D43 and D44) of tetraarylpyrrolo[3,2-b]pyrroles were prepared. They can be used without doping in the manufacture of the inverted planar perovskite solar cells. Tetraarylpyrrolo[3,2-b]pyrroles are accessible for one-pot synthesis.D42, D43 and D44 possess acceptor-π-donor-π-acceptor structure, on which the aryl bearing substitutes of cyan, fluorine and trifluoromethyl, respectively. Instead, the aryl moiety of D41 is in presence of methyl with a donor-π-donor-π-donor structure. The different substitutes significantly affected their molecular surface charge distribution and thin-film morphology, attributing to the electron-rich properties of fused pyrrole ring. The size of perovskite crystalline growth particles is affected by different molecular structures,and the electron-withdrawing cyan group of D42 is most conducive to the formation of large perovskite grains. The D42 fabricated devices with power conversion efficiency of17.3% and retained 55% of the initial photoelectric conversion efficiency after 22 days in dark condition. The pyrrolo[3,2-b]pyrrole is efficient electron-donating moiety for hole transporting materials to form good substrate in producing perovskite thin film.

Characterization of the Constructions Materials Used in the Hydroelectric Power Plants in the Sedano＇s Valley, Burgos （Spain）

Small hydropower plants for electricity generation were first built in Spain in the early 1880s. The Spanish peninsula is characterized by its rugged landscape, fast flowing rivers and steep gradients. A clear example of this is the remarkable area of the upper Ebro river basin where powerful water flows are found that are ideal for electricity generation. Between 1900 and 1930, the river Ebro was a major source of energy for industrial areas such as Alava, Vizcaya, Vitoria, Miranda de Ebro, Burgos and La Rioja. Between 1951-1965, the use of these small hydropower plants declined due to the construction of alternatives by industrialists in the Basque Country, which in most cases led to their deterioration. They were rescued in the late twentieth century, thanks to private sector initiatives which funded their rehabilitation. This study examines two small-scale hydraulic power plants in the province of Burgos at Medina de Pomar and at Quintanilla Escalada; both buildings were used for generating electricity and had living quarters for the workers and now represent historic architectonic and industrial heritage. The study documents their architectonic features and the restoration processes that have permitted one of them to remain in operation up until the present day.

金属有机骨架材料(MOFs)在饲料和畜产品中兽药残留检测中的应用

金属有机骨架材料(MOFs)作为目前少有的在样品前处理、仪器分析和快速检测领域都有良好应用的先进纳米材料,已逐渐成为饲料和畜产品中兽药残留和非法添加物检测技术的研究热点。饲料和畜产品中兽药残留和非法添加物通常面对的样品基质复杂、残留量低,因此也对检测技术提出了更高要求。文章以MOFs为研究对象,从检测要求的准确性、灵敏度、可操作性、环境友好性等几方面出发,综述了MOFs目前在饲料和畜产品中兽药残留检测各环节的最新研究进展,对MOFs的发展方向进行展望,为MOFs今后更好地应用于饲料安全监测和评价领域提供参考。

Growth interface of CdMnTe crystal by traveling heater method

The growth interfaces of CdMnTe（CMT） crystals grown by traveling heater method（THM） were studied. Two types of polycrystalline CMT feed ingots synthesized in a traditional rocking furnace and vertical Bridgman（VB） furnace were adopted in THM growth, and the effects of the polycrystalline feed on the growth interface were revealed. The morphology of the growth interface of CMT crystal（CMT2） grown from the feed by vertical Bridgman was smoother with lower curvature compared with that of CMT crystal（CMT1） from the feed by rocking furnace. The radial Mn composition and Te inclusion distribution of the CMT wafers were analyzed and correlated to the growth interface. The Mn segregation along the radial direction and Te inclusion density of CMT2 were lower than those of CMT1. The VB method synthesized polycrystalline feed could improve the growth interface morphology, which is beneficial for decreasing the Te inclusions and Mn segregation in CMT wafers.

FATIGUE DAMAGE CALCULATED BY RATIO-METHOD TO METALLIC MATERIALS WITH SMALL CRACK UNDER UNSYMMETRIC CYCLIC LOADING

Based on the standpoint to take for the crack size also to be a damage variable like the damage variable, by means of the two-directions coordinate system, several new calculation equations on the small crack growth rate are suggested for describing the elastic-plastic behavior of some metallic materials. And the estimation formulas of life are also suggested relative to varied small crack size at each loading history, which is unsymmetric cyclic loading. In the calculation method, as a loaded stress-strain parameter to adopt the ratio with plastic strain range to elastic strain range, and as the material constants using the typical material parameters in damage calculation expression, a new concept of the compositive material constant, which has functional relation with the typical material constants, average stress, average strain, critical loading time is given out. In addition, the fatigue damage of a part of car is put up to calculate as an example, its calculation results are accordant with the Landgraf＇s equation, and calculation precision is more rigorous, so could avoid unnecessary fatigue tests and will be of practical significance on saving times, manpower and capitals, as well as the convenience for engineering applications.

High-performance asymmetric small molecular donor materials based on indenothiophene for solution-processed organic solar cells

Two novel asymmetric organic small molecules of IT(2FBT-T3Cz)_2and IT(2FBT-TT3Cz)_2with an indenothiophene(IT)central donor core,fluorinated benzothiadiazole(2FBT)as acceptor and 3-carbazole(Cz)unit as terminal group were designed and synthesized as the donor materials in organic solar cells(OSCs).The thermal,optical absorption,electrochemical property,hole–electron mobility,film morphology were thoroughly studied.Using PC_(71)BM as an electron acceptor,without any additive and thermal annealing(TA)treatment,the IT(2FBT-T3Cz)_2-based cells showed a promising power conversion efficiency(PCE)of5.81%and the IT(2FBT-TT3Cz)_2-based cells exhibited a PCE of 4.39%.Our results demonstrate that the IT-based asymmetric small molecules can be developed as a promising class of donor materials for highperformance OSCs.

A case of postoperative recurrent intussusception associated with indwelling bowel tube

Intussusception is quite uncommon in adults.We report a rare case of a 76-year-old man with small bowel intussusception induced by two indwelling bowel tubes,the first a jejunal feeding tube and the second an ileus tube.After complete reduction of the first intussusception caused by the jejunal feeding tube and adhesion,reintussusception occurred due to the postoperative adhesion and ileus tube inserted into the bowel after the previous operation for intussusception.Finally,the part of the jejunum with re-intussusception and adhesion,including the place where the previous reduced intussusception had occurred,was resected.This case is a reminder that when there is no mucosal lesion other than an indwelling bowel tube or a hard adhesion/ inflammation around intussusception,the patient should be operated on without delay for resection of the intussusception to prevent re-intussusception,even if the resected bowel is predicted to be long.

THE ANTI-PLANE SHEAR FIELD IN AN INFINITE SLAB OF ELASTO-DAMAGED MATERIAL WITH A SEMI-INFINITE CRACK

This paper deals with an infinite slab with a semi-infinite crack,which is subjected to the anti-plane shear k_Ⅲ field at infinity.The slab is made of an elasto-damaged material.Analytical solution is obtained by use of conformal mapping.The shape of damaged-zone,the dissipative energy,the shear open- ing displacement on the crack surface and several stress distribution curves are given.The far field condition is checked,The asymptotic behavior near the crack-tip is given.

Technology Development and Production of Certain Chemical Platinum Metals Compounds at JSC ＂Krastsvetmet＂

In recent years JSC "Krastsvetmet" has successfully developed the production of chemically pure compounds of precious metals.Currently methods have been developed and facilities have been provided for industrial production of the following platinum metals compounds:Rhodium(Ⅲ) chloride hydrate,rhodium(Ⅲ) chloride solution,rhodium(Ⅲ) nitrate solution,rhodium(Ⅲ) iodide,rhodium(Ⅲ) sulfate,hydrated rhodium(Ⅲ) oxide,ammonium hexachlororodiate,rhodium(Ⅲ) phosphate solution,rhodium electrolytes;Iridium(Ⅳ) chloride hydrate,iridium(Ⅲ) chloride hydrate,ammonium hexachloroiridate(Ⅳ),hexa chloriridium acid solution,hexachloriridium crystalline acid;Ruthenium(Ⅲ) chloride hydrate,ruthenium(Ⅳ) hydroxide chloride,ruthenium(Ⅳ) hydroxide chloride solution,ammonium hexachlororuthenate,ruthenium(Ⅲ) chloride solution,potassium,diaquaoctachloronitrido diruthenate.The quality of the production meets the requirements of Russian and foreign consumers.

具有整体解的非齐次kirchhoff方程

证明了一个非齐次ｋｉｒｃｈｈｏｆ方程（带非局部项的非线性弦振动方程）的整体解的存在唯一性，推广了具有小初始资料的ｋｉｒｃｈｈｏｆ方程的已有结论．