Phase-Field Modeling for the Three-Dimensional Space-Filling Structure of Metal Foam Materials

Phase-field modeling for three-dimensional foam structures is presented. The foam structure, which is generally applicable for porous material design, is geometrically approximated with a space-filling structure, and hence, the analysis of the space-filling structure was performed using the phase field model. An additional term was introduced to the conventional multi-phase field model to satisfy the volume constraint condition. Then, the equations were numerically solved using the finite difference method, and simulations were carried out for several nuclei settings. First, the nuclei were set on complete lattice points for a bcc or fcc arrangement, with a truncated hexagonal structure, which is known as a Kelvin cell, or a rhombic dodecahedron being obtained, respectively. Then, an irregularity was introduced in the initial nuclei arrangement. The results revealed that the truncated hexagonal structure was stable against a slight irregularity, whereas the rhombic polyhedral was destroyed by the instability. Finally, the nuclei were placed randomly, and the relaxation process of a certain cell was traced with the result that every cell leads to a convex polyhedron shape.

基于石墨烯泡沫的电增强固相微萃取-高效液相色谱法测定鱼肉中3种磺胺类的残留

为提高鱼肉中磺胺类抗生素(sulfonamides,SAs)残留的富集效果,建立了基于氮掺杂三维石墨烯泡沫功能化整体柱(monolith@nitrogen-doped three-dimensional graphene foam,M@NGF)的电增强固相微萃取(electroenhanced solid phase microextraction,EE-SPME)方法,结合高效液相色谱技术,快速、灵敏地测定鱼肉中SAs残留。本研究采用原位聚合法,以离子液体为功能单体,NGF为导电增强剂,在不锈钢丝表面制备多孔M@NGF,建立EE-SPME方法,从鱼肉中萃取磺胺噻唑(sulfathiazole,ST)、磺胺二甲基嘧啶(sulfamethazine,SM_(2))和磺胺二甲氧嘧啶(sulfadimethoxypyrimidine,SMM)。对吸附时间、搅拌速度、吸附电压、离子强度、样品溶液p H值、解吸时间、解吸电压和解吸液组成进行了优化。结果表明,基于M@NGF的EE-SPME法对ST、SM_(2)和SMM的富集倍数分别为74、58和64,吸附平衡时间缩短至35 min。在5~5000μg/kg线性范围内,本方法对ST、SM_(2)和SMM的检出限分别为1.78、3.16μg/kg和1.84μg/kg,定量限均为5μg/kg,线性回归分析的决定系数(R^(2))均大于0.9990,加标回收率为79.2%~110.1%,相对标准偏差范围为1.4%~9.8%(n=5)。本方法解决了鱼肉中SAs残留萃取效率低、基质干扰严重的问题,实现了鱼肉中SAs残留的快速、灵敏检测。

Flow characteristics of three-phase foam in mine gob and its application

To study the flow characteristics of three-phase foam in gob area,different perfusion experiments in coal mine gob were designed and put forward in the paper.Through the observation of flow range,flow characteristics of three phase foam were analyzed with different flow rates.And,unsteady seepage process of three-phase foam was simulated with CFD software.Base on experiment and numerical simulation results,flow characteristics of three-phase foam and its major influence factors are discussed,and the optimal arrangement distribution of mine fire control drills is also determined.Research results show that the flow range and stacking height of three-phase foam in gob are significantly influenced by gravity.The vertical stacking height and horizontal diffusion distance of three-phase foam are also directly related to the flow volume of foam perfusion,the larger flow single hole perfusion volume,the higher stacking height and the longer diffusion distance could be obtained.

Bonding effect of liquid magnesium with open-celled carbon foam in interpenetrating phase composite

The issue of bonding formation in liquid metal/open-celled carbon foam(C_(of))systems was examined,taking into account the practical aspects of the synthesis of a new type of Mg-C metal material composite.The problem is complex due to the strong oxidation and intense evaporation of liquid magnesium,as well as the 3D geometry of the carbon component,where metal transport occurred through the foam cells’windows.Laboratory experiments performed at 700℃ in ceramic crucibles showed that spontaneous carbon foam infiltration by liquid metal is impossible under the applied conditions,either in an air atmosphere coupled with flux protection or under argon protection.Comparative tests performed in a UHV chamber filled with static pure Ar by a sessile drop method,coupled with non-contact heating and capillary purification at a test temperature of 700℃ directly in the UHV chamber,showed non-wetting behavior of the Mg/C_(of)couple with a correspondingly high contact angle of about 135°.The graphite capillary was then moved down,the liquid drop being slightly pressed into the foam,but these changes did not induce effective foam penetration.Despite the short contact time for the sessile drop test under an argon atmosphere,SEM+WDS analysis of the solidified Mg/C_(of)couple revealed the formation of an MgO interlayer at the interface,with a thickness of approx.1μm.The experimentally demonstrated presence of oxygen in the carbon foam sample,both before and after its contact with magnesium,points to oxide-type bonding being established between Mg and C_(of).This observation is in a good agreement with previous reports on the interface characterization of magnesium matrix composites reinforced with glassy carbon materials and carbon fibers by stir casting and pressure infiltration.Based on the findings of this study,a general structural scheme of the bonding process between carbon foam and liquid magnesium,as an important stage in the syntheses of Mg-C composites,was proposed.

Stabilized multifunctional phase change materials based on carbonized Cu-coated melamine foam/reduced graphene oxide framework for multiple energy conversion and storage

The leakage of organic phase change materials(OPCMs)at temperatures above their melting point severely limits their large-scale application.The introduction of porous supports has been identified as an efficient leakageproofing method.In this study,a novel carbonized Cu-coated melamine foam(MF)/reduced graphene oxide(rGO)framework(MF/rGO/Cu-C)is constructed as a support for fabricating stabilized multifunctional OPCMs.MF serves as the supporting material,while rGO and Cu act as functional reinforcements.As a thermal energy storage material,polyethylene glycol(PEG)is encapsulated into MF/rGO/Cu-C through a vacuum-assisted impregnation method to obtain PEG@MF/rGO/Cu-C composite with excellent comprehensive performance.PEG@MF/rGO/Cu-C exhibits high phase change enthalpies of 148.3 J g^(-1)(melting)and 143.9 J g^(-1)(crystallization),corresponding to a high energy storage capability of 92.7%.Simultaneously,MF/rGO/Cu-C endues the composite with an enhanced thermal conductivity of 0.4621Wm^(-1) K^(-1),which increases by 463%compared to that of PEG@MF.Furthermore,PEG@MF/rGO/Cu-C displays great light-to-thermal and electric-to-thermal conversion capabilities,thermal cycle stability,light-tothermal cycle stability,and shape stability,showing promising application prospects in different aspects.

A Single-phase of Supercritical CO_2/Polystyrene Solution in Foam Extrusion

The high quality single-phase solution of CO2/ Polystyrene was achieved,by analyzing the influential factors for polymer microcellular foaming extrusion.The curve of pressure distribution along the barrel was determined.The axial position of gas-injecting port on the barrel was chosen form the results of stable foaming,and the number of gas-injecting ports in the circumference of the barrel was determined from the CO2 solubility in polymer.The effect of the screw rotation speed on CO2 solubility was studied,and the effects of pressure difference between the gas and the polymer melt on gas-injecting process and on the foaming stability were investigated.The influence of the gas temperature before injection on the single-phase of CO2/Polystyrene solution also was studied.

DETERMINATION OF EFFECTIVE MODULI FOR FOAM PLASTICS BASED ON THREE PHASE SPHEROIDAL MODEL

The relations of bulk modulus, shear modulus, Young's modulus and the Poisson's ratio with porosity of foam plastics are determined by a three phase spheroidal model commonly used in Composite Mechanics. The results are compared with those using differential scheme. It is shown that the material properties derived from the present model normally are larger than those obtained by differential scheme for foam plastics with identical porosity. The differences in shear moduli and Young's moduli obtained by the two methods are small but they are larger for bulk moduli of incompressible matrix and Poisson's ratios. The Young's moduli of high density foam plastics derived by the present model agree better with experimental ones.

Molten Salts/Ceramic-Foam Matrix Composites by Melt Infiltration Method as Energy Storage Material

A new type of high temperature energy storage material was obtained through the melt infiltration method, using compounding SiC ceramic foam as matrix and Na2SO4 as phase change material. The resulting composite material was measured by XRD, SEM, TG-DSC methods. The experimental results indicate that the composite is composed of silicon carbide, sodium sulfate and square quartz, and no chemical reactions occurs between Na2SO4 and SiC matrix. Na2SO4 has a good bonding with the SiC ceramic foam matrix. As the composite material is characterized by high thermal energy storage density and high thermal conductivity, it is suit for energy storage under high temperature.

An efficient preparation of porous polymeric microspheres by solvent evaporation in foam phase

This paper reports an efficient method of preparing porous polymeric microspheres by solvent evaporation in foam phase,in which phase separation between polymer and porogen occurs in foam phase instead of that in water phase by using the traditional solvent eva poration method.The method provides outstanding features,including being time-saving,of high-yield and able for continuous production,in which formation of porous polymeric microspheres finished within 3 min with a high production yield up to approximate 95 wt% and the process was able to be developed into a continuous process for production of porous polymeric microspheres.It was also universal to non-crosslinked polymers since the method is a development on the traditional emulsion solvent evaporation method.The new method is efficient and can be used potentially on the industrial scale for continuous production of porous polymeric microsphere s.

A Phase II Study of Antineoplastons A10 and AS2-1 in Children with High-Grade Glioma. Final Report (Protocol BT-06), and Review of Recent Trials

Standard treatment for high-grade glioma involves surgical resection followed by radiation therapy and temozolomide. Unfortunately, there are no standard treatment recommendations after recurrence and new therapies are needed for patients whose tumor recurs after first-line treatment. This single-arm, two-stage, interventional Phase II study evaluated the efficacy and safety of a combination of antineoplastons A10 and AS2-1. Nineteen patients were enrolled in the study (safety population), but fifteen patients with a median age of 9.4 years who met eligibility criteria were evaluated. The majority of subjects (12/15) were Caucasian and 8/15 (53%) were female. More than half (53%) of patients were diagnosed with glioblastoma and 33% with anaplastic astrocytoma. All patients had failed standard therapy including surgery, radiation, and chemotherapy. Antineoplastons were administered intravenously every four hours (median dose of A10 6.9 g/kg/d and AS2-1 0.30 g/kg/d) until objective response was documented and thereafter for a further 8 months. Clinical evaluations were performed every 8 weeks. All patients enrolled in the study were included in the safety analysis but only patients fulfilling the inclusion criteria were included in the efficacy evaluation. The duration of treatment with antineoplastons ranged from 2 weeks to 120 weeks. A complete response was documented in 2/15 (13%), partial response in 2/15 (13%), stable disease in 3/15 (20%). Progression-free survival at six months was 47% and overall survival (OS) at one year was 33.3%. One patient (6.7%) survived 10 years from treatment start. A small group of patients suffered reversible Grade 3 and 4 toxicities including hypernatremia 2/19 (11%) and decrease of neutrophils 1/19 (5%). There were no chronic toxicities. There was improvement of quality of life in patients who had objective response. It is concluded that antineoplastons show efficacy with an acceptable profile in this cohort of patients with recurrent high-grade glioma.

A Phase II Study of Antineoplastons A10 and AS2-1 in Adult Patients with Recurrent Glioblastoma Multiforme: Final Report (Protocol BT-21)

Treatment of recurrent glioblastoma multiforme (RGBM) creates one of the most difficult challenges to neuro-oncology. The purpose of this study is to evaluate the outcome of adults with high-grade glioma with special attention to RGBM patients treated with Antineoplastons (ANP) A10 and AS2-1 injections. The study was conducted according to Protocol BT-21, which accrued patients who failed standard radiation therapy (RT) and chemotherapy. There were 40 candidates registered in the study. Among the intent-to-treat (ITT) population, there were 30 cases of RGBM that progressed during and after prior treatment, 4 patients with anaplastic astrocytoma (AA), 1 with anaplastic mixed glioma (AMG), and 5 with persistent GBM. The aim of this paper is to evaluate the responses, survival and toxicity of all 40 patients, the efficacy in 30 patients with RGBM, and in 24 patients with RGBM who received at least 28 days of ANP (ERGBM). All RGBM patients were treated before with RT and chemotherapy, except one patient who only had surgery (patient refused radiation). In this group, 63% had one recurrence, 30% had two recurrences, and 7% had three recurrences. The median duration of ANP and ITT was 12 weeks and the median dosage of ANP A10 was 6.52 g/kg/d and ANP AS2-1 was 0.23 g/kg/d. Responses were assessed by gadolinium-enhanced magnetic resonance imaging (MRI) repeated every eight weeks. In the ITT population, objective responses (ORs) were determined in 10% of cases (complete response—CR, and partial response—PR in 5% each). Progression-free survival (PFS) in ITT at six months was 17.5%. Overall survival (OS) was 28.3% at one year, 2.6% at two years, five and ten years. In the RGBM population, objective responses (ORs) were determined in 13.3% of cases (CR and PR in 6.7% each). PFS in RGBM at six months was 16.7%. OS was 34.7% at one year, 3.47% at two years, five?and ten years. In the ERGBM population, ORs were determined in 16.7% of cases (CR and PR in?8.3% each). PFS in ERGBM at six months was 20.8%, OS was 39.3% at one year, 4.4% at two years, five and ten years. The treatment was well-tolerated with reversible Grades 3 and 4 toxicity in 17.5% of patients (7 patients who experienced multiple toxicities) and no chronic toxicity. In conclusion, the study reached efficacy endpoint. ANP is well-tolerated and compares favorably to the current treatment for RGBM.

Thermodynamic modeling and phase diagram prediction of salt lake brine systemsⅡ.Aqueous Li^(+)-Na^(+)-K^(+)-SO_(4)^(2-) and its subsystems

It is still a challenging task to accurately and temperature-continuously express the thermodynamic properties and phase equilibrium behaviors of the salt-lake brine with multi-component,multitemperature and high concentration.The essential subsystem of sulfate type brine,aqueous Li^(+)-Na^(+)-K^(+)-SO_(4)^(2-) and its subsystems across a temperature range from 250 K to 643 K are investigated with the improved comprehensive thermodynamic model.Liquid parameters(Δg_(IJ),Δh_(IJ),and ΔC_(p,IJ))associated with the contributions of Gibbs energy,enthalpy,and heat capacity to the binary interaction parameters,i.e.the temperature coefficients of eNRTL parameters formulated with a Gibbs Helmholtz expression,are determined via multi-objective optimization method.The solid constantsΔ_(f)G_(k)°^((298.15))andΔ_(f)H_(k)°^((298.15))of11 solid species occurred in the quaternary system are rebuilt from multi-temperature solubilities.The modeling results show the accurate representation of(1)solution properties and binary phase diagram at temperature ranges from eutectic points to 643 K;(2)isothermal phase diagrams for Li_(2)SO_(4)-Na_(2)SO_(4)-H_(2)O,Li_(2)SO_(4)-K_(2)SO_(4)-H_(2)O and Na_(2)SO_(4)-K_(2)SO_(4)-H_(2)O ternary systems.The predicted results of complete structure and polythermal phase diagram of ternary systems and the isothermal phase diagrams of quaternary system excellently match with the experimental data.

A Phase II Study of Antineoplastons A10 and AS2-1 in Children with Recurrent, Refractory or Progressive Primary Brain Tumors—Final Report (Protocol BT-22)

Primary malignant brain tumors are a leading cause of cancer-related death in children. This Phase II study evaluated the efficacy and safety of Antineoplastons A10 and AS2-1 (ANP) in children who developed progression during standard treatment. A total of 43 children were recruited to the study, but only 41 met eligibility criteria. There were twelve cases of glioblastoma multiforme (GBM), eight anaplastic astrocytomas (AA), twelve diffuse intrinsic pontine gliomas (DIPG), three supertentorial primitive neuroectodermal tumors (sPNET), three cases of medulloblastoma and one case each of anaplastic ependymoma (AE), atypical teratoid rhabdoid tumor (AT/RT), and disseminated pilocytic astrocytoma (PAD). ANP was administered intravenously daily every four hours (median dose of A10 8.74 g/kg/d and AS2-1 0.35 g/kg/d), until objective response (OR) was documented, and then a further eight months. All enrolled patients were included in safety, but only eligible patients in the efficacy evaluation. A total of 12.2% of patients obtained OR;2.4% complete response (CR) and 9.8% partial response (PR). Stable disease (SD) was determined in 17.1% and progressive disease (PD) in 43.9% of cases. There were 26.8% of nonevaluable (NE) cases due to premature discontinuation. Out of five OR cases, four patients were diagnosed with recurrent DIPG and one with recurrent AA. Median progression-free survival (PFS) was 2.5 months. Median overall survival was 4.8 months. OS at 6 months was 46.3%, one year was 12.2%, and 4.8% at two, five, and ten years. The longest survivor is a patient diagnosed with DIPG and gliosarcoma who remains alive more than 15 years. A group of eleven patients reported grade 3 and 4 toxicity including hypernatremia in eight cases, somnolence in two cases, and hypokalemia in one case. There were no chronic toxicities, and the quality of life was very good. The largest group of patients were represented by DIPG, GBM, and AA. The best results were obtained in the DIPG and AA groups. In the DIPG group, CR was in 8.3%, PR was 25%, median PFS was 4.8 months, median OS was 6.1 months, and OS at 6 months was 58.3%, at one year 25%, and 8.3% at two, five, and ten years. In the AA group, PR was 12.5%, median PFS was 3.7 months, median OS was 4.7 months, and OS at 6 months was 37.5%, and 12.5%, at one, two, five, and ten years. In conclusion, antineoplastons showed efficacy and acceptable toxicity in patients with recurrent, refractory or progressive primary brain tumors.

A Phase II Study of Antineoplastons A10 and AS2-1 in Patients with Brainstem Gliomas. The Report on Non-Diffuse Intrinsic Pontine Glioma (Protocol BT-11)

Inoperable brainstem gliomas (BSG) are among the most difficult to treat malignancies. In the intent-to-treat (ITT) population of the BT-11 study for BSG, forty patients (median age 11.2 years old) were enrolled. Antineoplastons A10 and AS2-1 (ANP) were administered intravenously daily. The median daily dose of A10 was 8.70 g/kg/day and AS2-1 was 0.32 g/kg/day. Efficacy analyses were conducted in two subgroups: recurrent pediatric diffuse intrinsic pontine glioma (RPDIPG, N?= 17) and non-diffuse intrinsic pontine glioma (NDIPG, N?= 11). This paper reports the results of the study of the efficacy and safety of ANP in patients with NDIPG. The results in the RPDIPG group were reported before;complete response (CR) was 6%, partial response (PR) 23.5%, and stable disease (SD) 17.6%. One year overall survival (OS) was 29.4%, 2 years 11.8%, and 5, 10, and 15 years 6%. In the NDIPG group, there were 36% CR and 27.5% SD. OS at 1, 5, 10, and 15 years was 82%, 73%, 62%, and 50% correspondingly. There was only one serious adverse event (9%) reported in NDIPG represented by hypokalemia, Grade 4. The results suggest that ANP shows efficacy and an acceptable tolerability profile in patients with RPDIPG and NDIPG.

Effects of copper content on microstructure and mechanical properties of open-cell steel foams

The effects of copper content on the microstructural and mechanical properties of steel foams are investigated. Spherical urea granules, used as a water-leachable space holder, were coated with a mixture of iron, ultrafine carbon, and different amounts of copper powders. After the mixture was compacted and the space holder was removed by leaching, a sintering process was performed under an atmosphere of thermally dissociated ammonia. Microstructural evaluations of the cell walls were carried out using optical microscopy and scanning electron microscopy in conjunction with energy-dispersive X-ray spectroscopy. In addition, compression tests were conducted to investigate the mechanical properties of the manufactured steel foams. The results showed that the total porosity decreases from 77.2% to 71.9% with increasing copper content in the steel foams. In the foams' microstructure, copper islands are mostly distributed in pearlite and intergranular carbide phases are formed in the grain boundaries. When the copper content was increased from 0 to 4 wt%, the elastic modulus, plateau stress, fracture stress, and fracture strain of manufactured steel foams improved 4.5, 6, 6.4, and 2.5 times, respectively.

Synergistic Effect in Mixed Capillary Gas Chromatographic Stationap Phases Containing Heptakis(2,3,6-tri-o-pentyl)-β-cyclodextrin and Dibenzo-18-crown-6

used－silical capillary columns containing heptakis（2、3、6－tri－o－pentyl）-β-cyclodextrinand dibenzo-18-crown-6 were prepared．By studying the selectivity of mixed stationary phases forsome solute pairs.as well as comparing with the heptakis（2．3、6-tri-O-pentyl）-β-cyclodextrin and thedibenzo-18-crown-6 used as individual stationary phase、the synergistic effects were observed.These effects were affected by the column temperature．mixed ratio and linear velocity of carrier gas．

A Modified Kelvin Model for Thermal Performance Simulation of High Mechanical Property Open-Cell Metal Foams

This paper proposes a modified Kelvin model for high mechanical property open-cell metal foams and investigates its application in thermal simulations. The thermal conductivity is simulated based on the steady state method and the results are consistent with experimental values. The melting process of phase change materials (PCMs) in Kelvin model and its modified model is numerically investigated under a temperature constant heat resource. By detecting the temperature variations, it shows that the metal foam greatly improves the heat transfer in energy storage systems. Besides, the comparison of the melting process in two foam models indicates that the systems based on high mechanical property metal foams have a shorter melting time. The melting process of paraffin in modified Kelvin metal foam models with three different porosities (65%, 70% and 75%) are numerically analyzed and compared.

A Phase II Study of Antineoplastons A10 and AS2-1 in Children with Low-Grade Astrocytomas—Final Report (Protocol BT-13)

Nonresectable Low-Grade Astrocytomas (LGA) can compromise function and threaten life. For the majority of patients, the most appropriate strategy is initial chemotherapy followed by Radiation Therapy (RT). Since curative treatment is not available for most of these patients, it is reasonable to conduct clinical studies to evaluate new agents. This Phase II study evaluates efficacy and safety of Antineoplastons A10 and AS2-1 (ANP) in LGA. Sixteen children diagnosed with LGA were treated. They included 12 males and 4 females, ages 1.6 - 17.4 years (median 10.6). Efficacy was evaluated in 16 patients. The majority of patients were previously treated, but 1 patient had stereotactic biopsy only. Out of the remaining 15 patients, 6 patients received chemotherapy, and 7 patients had surgery, and 2 patients received RT and chemotherapy after surgery. The patients received treatment with ANP administered daily every 4 hours (median dose of A10 was 7.71 g/kg/d and AS2-1 was 0.26 g/kg/d) until objective response or stable disease was documented and for 8 months thereafter. The duration of ANP IV ranged from 1.4 to 286 weeks with a median of 83 weeks. A complete response was documented in 25.0%, partial response in 12.5%, and stable disease in 37.5%. Overall survival was 67.7% at 5 years, and 54.2% at 10 and 15 years. Progression-free survival was 48.1%, 34.4% and 34.4% at 5, 10, and 15 years respectively. The treatment was associated with grade 3 or grade 4 Adverse Drug Experiences (ADE) in 6 patients. There were two hypernatremias of grade 4 (12%). Grade 3 ADE included urinary frequency (6%), fatigue (6%) and hypernatremia (6%). There were no chronic toxicities, and there was a high quality of survival. ANP shows efficacy with a very good toxicity profile in this cohort of children with low-grade astrocytoma.

Solid-phase Synthesis of-Haloaldehydes from Polymer-supported 4-(Phenylseleno)morpholine

Polystyrene-supported 4-(phenylseleno)morpholine was synthesized and could be used as an efficient ?selenenylating agent for saturated aldehydes. ?Haloaldehydes were prepared by reaction of polystyrene-supported ?selenoaldehydes with bromine or sulfuryl chloride in good yield and high purity.

X-ray diffraction study of effect of deposition conditions on α-β phase transition and stress evolution in sputter-deposited W coatings

Pure W and W-Cu-W trilayer coatings were deposited on an Fe substrate by d.c. magnetron sputtering. The α-β phase evolution, intragranular stress evolution in sputter-deposited W layer were investigated by x-ray diffraction. They are directly related to the film microstructure, density and adhesion. Therefore, control of the film stress and phase component transition is essential for its applications. The phase component transition from β-W to α-W and intragranular stress evolution from tensile to compressive strongly depend on the deposition parameters and can be induced by lowering Ar pressure and rising target power. The compressively stressed films with α-W phase have a dense microstructure and high adhesion to Fe substrate.