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A Possible Alternative to the Accelerating Universe III

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Journal of Modern Physics 2016年第13期7卷 1829-1844页

作者： frank r. Tangherlini San Diego CA USA

This work extends the author’s two previous works (2015), Journal of Modern Physics, 6, 78-87, and 1360-1370, by obtaining the index of refraction n of the dark energy for additional values of the cosmological density parameters, and for the two methods of obtaining n: least squares fit, and electromagnetic theory. Comparison of the alternative model with the accelerating universe for the new values of the density parameters and n is given in two tables. The new values for n are used to obtain a range of ages for the Einstein de Sitter (EdS) universe. It is shown that the EdS universe must be older than the comparison accelerating universe. This requirement is met for the Planck 2015 value of the Hubble constant, corrected for the speed of light reduction by n. A supporting measurement as well as a disagreeing measurement is also discussed. Possible support from a stellar age determination is also discussed. It is shown that the expression obtained earlier for the increased apparent magnitude of the SNe Ia provides as good a fit for a closed universe with Ω(tot = 1.005) , as it does for the flat EdS universe. Comparison is presented in a third table. An upper bound on ΩΛ is given for a closed universe that eventually collapses back on itself that is too small for the value needed for the accelerating universe.

关键词： Dark Energy Speed of Light Age of Universe Closed Universe

6-相步光弹仪测试细纤维/树脂基体相界面剪应力

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江苏大学学报（自然科学版） 2010年第1期31卷 40-44页

作者：刘政袁新华 frank r Jones Ceramics and Composites Laboratory Department of Engineering MaterialsUniversity of Sheffield 江苏大学材料科学与工程学院江苏镇江212013

用新型的6-相步光弹仪,对直径25μm的单玻璃纤维增强环氧树脂复合材料的纤维-树脂相界面微观应力分布进行测试.相步弹性学分析表明纤维末端和纤维断裂处附近的等级条纹级数较高,存在较大的应力集中区域.试样两端加载18.38,25.61和32.53... 详细信息

用新型的6-相步光弹仪,对直径25μm的单玻璃纤维增强环氧树脂复合材料的纤维-树脂相界面微观应力分布进行测试.相步弹性学分析表明纤维末端和纤维断裂处附近的等级条纹级数较高,存在较大的应力集中区域.试样两端加载18.38,25.61和32.53MPa时,纤维末端相界面剪应力最大值分别出现在距纤维末端7,18和33μm处,为26.87,30.22和33.20MPa.纤维断裂处,加载为24.69MPa时,相界面剪应力最大值出现在距纤维断裂25μm处,约30MPa;加载增加到33.09MPa时,高的等级条纹级数区域向远离纤维断裂处延伸,相界面剪应力最大值增加到约36MPa.

关键词： 6-相步光弹仪相界面剪应力等级条纹级数等倾角

Breakthrough in the challenging P450-catalyzed chemoenzymatic synthesis of C14-functionalized steroids

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中国科学:化学英文版 2023年第9期66卷 2435-2436页

作者： Manfred T.reetz frank Hollmann Max-Planck-Institut für Kohlenforschung Kaiser-Wilhelm-Platz 145480 MülheimGermany Tianjin Institute of Industrial Biotechnology Chinese Academy of SciencesTianjin 300308China Department of Biotechnology Delft Universityvan der Maasweg 92629 HZ DelftNetherlands

Intensive past research has demonstrated that cytochrome P450 monooxygenases are involved in the biosynthesis of numerous natural products and in human metabolism of various pharmaceuticals [1]. This inspired synthetic organic and pharmaceutical chemists to test them as catalysts in the oxidative hydroxylation of steroids. Unfortunately, wildtype P450s generally proved to show low levels of regio-and diastereoselectivity as well as suboptimal activity.

关键词： steroids catalyzed synthesis

High-quality perovskite MAPbI_3 single crystals for broad-spectrum and rapid response integrate photodetector

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Journal of Energy Chemistry 2018年第3期27卷 722-727页

作者： Yunxia Zhang Yucheng Liu Zhou Yang Shengzhong(frank)Liu Key Laboratory of Applied Surface and Colloid Chemistry National Ministry of Education Shaanxi Key Laboratory for Advanced Energy Devices ShaanxiEngineering Lab for Advanced Energy TechnologyInstitute for Advanced Energy MaterialsSchool of Materials Science and EngineeringShaanxi Normal UniversityXi'an 710119ShaanxiChina iChEM Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

Organic–inorganic single-crystalline perovskites have attracted significant attentions due to their exceptional progress in intrinsic properties＇ investigation and applications in photovoltaics and optoelectronics. In this study, the large perovskite CH3NH3PbI3 single crystal with the largest length of 80 mm was prepared through the method of inverse-temperature crystallization. Meanwhile, the mass production of integrate photodetectors have been fabricated on the single-crystalline wafer and the photoresponse performances were investigated. The results show that the single-crystalline photodetectors have broad spectrum response to 900 nm, rapid response speed（〈40 μs） and excellent stability. These findings are of great importance for future promising perovskite single crystalline for integrated photoelectronic application.

关键词： Single-crystalline Perovskite Photodetector rapid response

Path towards high-efficient kesterite solar cells

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Journal of Energy Chemistry 2018年第4期27卷 1040-1053页

作者： Dongxiao Wang Wangen Zhao Yi Zhang Shengzhong(frank)Liu Institute of Photoelectronic Thin Film Devices and Technology and Key Laboratory of Photoelectronic Thin Film Devices and Technology Tianjin Nankai UniversityTianjin 300071China Key Laboratory for Applied Surface and Colloid Chemistry National Ministry of EducationShaanxi Engineering Lab for Advanced Energy TechnologySchool of Materials Science and EngineeringShaanxi Normal UniversityXi'an 710062ShaanxiChina Dalian National Laboratory for Clean Energy iChEM(Collaborative Innovation Center of Chemistry for Energy Materials)Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023.LiaonigChina

Kesterite structure semiconductor Cu2ZnSn（S,Se）4 is one of the most promising candidate as a light absorber material to overtake the next generation of thin film solar cells, owing to its low cost, non-toxic, and earth abundant source materials. The Sbockley-Queisser limit of the single junction Cu2ZnSn（S,Se）4 solar cell is over 30%, signifying a large potential of this family of solar cells. In the past years, with the development of synthesis techniques, Cu2ZnSn（S,Se）4 solar cells have attracted considerable atten- tion and the power conversion efficiency of Cu2ZnSn（S,Se）4 solar cell has experienced a rapid progress. Presently, the certified champion efficiency of CZTSSe solar cells has reached to 12.6%, which is far below the efficiency of Cu（ln,Ga）Se2 solar cell. In this review, the developments of Cu2ZnSn（S,Se）4 solar cells in recent years are briefly reviewed. Then the fundamental understanding of Cu2ZnSn（S,Se）4 solar cells is introduced, including materials and device structure, as well as the band alignment of hetero-junction and their impacts on device performance. After that, we mainly review the progress and achievements in the preparation processes, through vacuum and non-vacuum based processes. Finally, we outline the challenges and perspectives of this promising solar cell.

关键词： Kesterite CZTS Thin film solar cells

Pore characterization of PM Mg–0.6Ca alloy and its degradation behavior under physiological conditions

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Journal of Magnesium and Alloys 2021年第2期9卷 686-703页

作者： Eshwara Phani Shubhakar Nidadavolu Diana Krüger Berit Zeller-Plumhoff Domonkos Tolnai Björn Wiese frank Feyerabend Thomas Ebel regine Willumeit-römer Division Metallic Biomaterials Institute of Materials ResearchHelmholtz-Zentrum GeesthachtMax-Planck-Str.1Geesthacht 21502Germany Magnesium Innovation Center(MagIC) Institute of Materials ResearchHelmholtz-Zentrum GeesthachtMax-Planck-Str.1Geesthacht 21502Germany

Several material parameters affect degradation characteristics of Mg and its alloys under physiological *** Mg materials are interesting for their simultaneous degradation and drug delivery ***,an increase in pore surface area is detrimental to both degradation resistance and subsequent mechanical *** present work aims at determining the threshold porosity value in Mg–0.6 Ca specimens produced by powder metallurgy(PM)below which low degradation rates persist with acceptable mechanical *** different porous Mg–0.6 Ca specimens containing both closed and open pore structures were fabricated with porosities ranging from 3%to 21%.Degradation profiles were obtained via a semi static immersion test over 16 days under physiological conditions using Dulbecco’s modified Eagle’s medium with Glutamax and 10%fetal bovine serum as *** results are related to morphological pore parameters like pore size distribution,pore interconnectivity and pore curvatures that were quantified using an ex situμCT *** general,with decreasing porosity a decrease in pore interconnectivity is seen followed by rounding of the *** degradation rates(MDrr)are observed in specimens until 10%porosity,however,the upper bound for reproducible degradation is observed to be in specimens until 12%*** porosity level also marks the transition from closed to open pore nature with a simultaneous change in pore interconnectivity from less than 10%to greater than 95%,below and above this porosity level,*** tensile strength and elongation to failure recorded for specimens with 10%porosity were 70 MPa and 2%,respectively displaying positive traits of both homogenous degradation and mechanical *** results suggest that high pore interconnectivity is the dominant factor controlling degradation and mechanical properties in porous Mg-0.6 Ca *** results also indicate a good sintering respons

关键词： Porous Mg-0.6Ca In vitro Degradation μCT Sintering

Dietary nano chromium picolinate can ameliorate some of the impacts of heat stress in cross-bred sheep

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Animal Nutrition 2021年第1期7卷 198-205页

作者： Alex T.Hung Brian J.Leury Matthew A.Sabin Fahri Fahri Kristy DiGiacomo Tu-Fa Lien frank r.Dunshea Faculty of Veterinary and Agricultural Sciences The University of MelbourneParkvilleVIC3010Australia Murdoch Children's research Institute The University of MelbourneParkvilleVIC3010Australia Department of Animal Science National Chiayi UniversityChina Faculty of Biological Sciences The University of LeedsLeeds LS29JTUnited Kingdom

Two studies were conducted to evaluate the effect of nano chromium picolinate(nCrPic)during heat stress(HS)in *** the initial study,36 Merino×Poll cross-bred sheep were individually penned and allocated to 3 dietary treatments(0,400 and 800μg/kg nCrPic)for 8 *** composition was determined at the beginning and end of the experiment using dual energy X-ray *** sheep remained in their dietary groups but were then placed in metabolic cages and randomly allocated within the dietary group to differing ambient temperature regimes,i.e.,thermo-neutral(TN)(n=18)and HS(n=18),for 3 *** nCrPic had no effect on growth performance and body composition during the initial study conducted under TN *** stress decreased average daily feed intake(ADFI)(P=0.002)whereas sheep under HS had reduced average daily gain(ADG)and indeed lost weight(Pry nCrPic increased both ADFI(P=0.041)and ADG(P=0.049)under both TH and HS conditions such that the performance of sheep receiving supplemental nCrPic and exposed to HS was similar to that of control sheep maintained under TN *** stress increased rectal temperature(Prespiration rate(Prticularly during the hottest parts of the day as indicated by interactions(Prmal *** temperature was lower in sheep fed nCrPic(P=0.050),particularly under peak HS conditions during the afternoon as indicated by the interactions between dietary nCrPic and time of day(Pry nCrPic,thermal treat-ment and time of day(P=0.010).Similarly,respiration rate was lower in sheep fed nCrPic under peak HS conditions during the afternoon as indicated by the interactions between dietary nCrPic and thermal treatment(Pry nCrPic and time of day(P=0.030).In conclusion,dietary nCrPic can partially ameliorate the negative effects of HS as indicated by the maintenance of ADFI and decreased physiological responses,such as elevatio

关键词： Chromium picolinate Sheep Heat stress Nanotechnology Physiology

A Possible Solution to the Disagreement about the Hubble Constant

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Journal of Modern Physics 2018年第9期9卷 1827-1837页

作者： frank r. Tangherlini San Diego CA USA

The current disagreement about the Hubble constant H0 was described as a “Crisis in Cosmology”, at the April (2018) Meeting of the American Physical Society, and hence its resolution is of utmost importance. This work proposes that the solution to the disagreement between the Planck Collaboration cosmic microwave background (CMB) value of H0, together with the very close BOSS Collaboration baryon acoustic oscillation (BAO) value, and the significantly higher value of H0 found by the SHOES Collaboration cosmic distance ladder (CDL) work, is due to the fact that the CMB and BAO values of H0 are not for an accelerating universe, as generally believed, but are actually the values for a decelerating universe. In contrast, the CDL value of H0 is indeed that for an accelerating universe. It is shown that by replacing the negative deceleration parameter in the expression for logH0 in the CDL work by a positive deceleration parameter, the value of H0 can be brought down to agree with the CMB and BAO lower values. There is a brief review of the author’s decelerating model based on the Einstein de Sitter universe, augmented by a model of dark energy that does not have a negative pressure, but instead has a non-dispersive index of refraction n, causing the speed of light through the dark energy of intergalactic space to be reduced to c/n. As reported earlier, this assumption is sufficient to accommodate the increase in apparent magnitude of the Type Ia supernovae (SNe Ia). Additional support for the model is presented, together with a proposal for astronomical falsification.

关键词： Hubble Constant Disagreement CMB & BAO Determinations Decelerating Interpretation CDL Determination & Modification

A Possible Alternative to the Accelerating Universe II

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Journal of Modern Physics 2015年第9期6卷 1360-1370页

作者： frank r. Tangherlini P.O. Box 928211 San Diego CA 92192 USA

This work revises and extends the author’s previous work (2015), Journal of Modern Physics, 6, 78- 87, by proposing that the index of refraction n of intergalactic space (IGS) is of electromagnetic origin. This leads to a theoretical expression for n that agrees very well with the least squares value obtained previously. A table comparing the fractional distance increase predicted by the two differently obtained indices is given. This revised view requires that the high energy charged particles found in cosmic rays originate from high energy neutral particles, presumably high energy gamma rays, that were able to travel through the IGS without energy loss due to Cherenkov radiation. An alternative explanation for the counter indication from the IceCube findings of Abassi, r., et al. (2012) Nature, 484. 351-353 is proposed, which might also explain the findings of Aartsen et al. (2013) Physical review Letters, 111, 021103. Since the model predicts galaxies act as divergent lenses, a geometrical analysis and corresponding figure describing this effect is given, as well as a table for a range of angles to the image galaxy relative to the direction to a target galaxy that is divergently lensed. The reduction of the speed of light in the IGS leads to a revision of the Planck (2015) value of the Hubble constant of ~68 km·s-1·Mpc-1 to ~47 km·s-1·Mpc-1, and hence an age for the Einstein-de Sitter universe greater than that of the oldest white dwarfs in the Galaxy, thereby resolving a long-standing problem with this model of the universe.

关键词： Speed of Light Cosmic rays Divergent Lensing Hubble Constant