40,709 research outputs found
Development of new proton conducting materials for intermediate temperature fuel cells
No full textThe work in this thesis mainly focuses on the preparation and characterization of several phosphates and solid oxide systems with the aim of developing new proton conducting materials for intermediate temperature fuel cells (ITFCs). Soft chemical methods such as sol-gel methods and conventional solid state methods were applied for the synthesis of these materials.
Aluminum phosphate obtained by a solution method is single phase and belongs to one of the Al(H₂PO₄)₃ allotropies with hexagonal symmetry. The material is stable up to 200°C and decomposes into Al(PO₃)₃ at a higher temperature. The electrical conductivity of pure Al(H₂PO₄)₃ is on the order of 10⁻⁶-10⁻⁷ S/cm, very close to the value for the known proton conductors AlH₃(PO₄)₂•3H₂O and AlH₂P₃O₁₀•2H₂O. Much higher conductivity is observed for samples containing even a trace amount of excess H₃PO₄. It is likely that the conduction path gradually changes from grain interior to the surface as the acid content increases. The conductivity of Al(H₂PO₄)₃-0.5H₃PO₄ exhibited a good stability over the measured 110 hours.
Although tin pyrophosphate (SnP₂O₇) has been reported to show a significantly high conductivity (~10⁻² S/cm) at 250°C in various atmospheres, we observed large discrepancies in the electrical properties of SnP₂O₇ prepared by different methods. Using an excess amount of phosphorous in the synthetic procedure generally produces SnP₂O₇ with much higher conductivity (several orders of magnitude higher) than samples with stoichiometric Sn:P ratios in their synthetic procedure. Solid state ³¹P NMR confirmed the presence of residual phosphoric acid for samples with excess starting phosphorous. Transmission Electron Microscope (TEM) confirmed an amorphous layer covered the SnP₂O₇ granules which was probably phosphoric acid or condensed phases. Thereby, it is quite likely that the high conductivity of SnP₂O₇ results mainly from the contribution of the residual acid. The conductivity of these samples exhibited a good stability over the measured 80 hours.
Based on the observations for SnP₂O₇, we developed a nano core-shell structure based on BPO₄ and P₂O₅ synthesised by solid state methods. The particle size of BPO₄ using this method varied between 10-20 nm depending on the content of P₂O₅. TEM confirmed the existence of an amorphous layer that is homogeneously distributed. The composite exhibits the highest conductivity of 8.8×10⁻² S/cm at 300°C in air for 20% extra P₂O₅ and demonstrates a good stability during the whole measured 110 hours. Polytetrafluoroethylene (PTFE) was introduced into the composites in order to increase malleability for fabrication. The conductivity and mechanical strength were optimized by adjusting the PTFE and P₂O₅ content. These organic-inorganic composites demonstrate much better stability at elevated temperature (250°C) over
conventional SiC-H₃PO₄-PTFE composites which are common electrolytes for phosphoric acid fuel cells (PAFCs). Fuel cells based on BPO₄-H₃PO₄-PTFE composite as the electrolyte were investigated using pure H₂ and methanol as fuels. A maximum power density of 320 mW/cm² at a voltage of 0.31 V and a maximum current density of 1.9 A/cm² at 200°C were observed for H₂/O₂ fuel cells. A maximum power density of 40 mW/cm² and maximum current of 300 mA/cm² 275°C were observed when 3M methanol was used in the cell.
Phosphoric acid was also introduced into materials with internal open structures such as phosphotungstic acid (H₃PW₁₂O₄₀) and heteropolyacid salt ((NH₄)₃PW₁₂O₄₀), for the purpose of acquiring additional connections. The hybrids obtained have a cubic symmetry with enlarged unit cell volume, probably due to the incorporation of phosphoric acid into the internal structures. Solid state ³¹P NMR performed on H₃PW₁₂O₄₀-xH₃PO₄ (x = 0-3) showed additional peaks at high acid content which could not assigned to phosphorus from the starting materials, suggesting a strong interaction between H₃PW₁₂O₄₀ and H₃PO₄. The conductivity of hybrids was improved significantly compared with samples without phosphoric acid. Fourier transform infrared spectra (FT-IR) suggest the existence of large amount of hydrogen bonds (OH••••O) that may responsible for the high conductivity. A H₂/O₂ fuel cell based on H₃PW₁₂O₄₀-H₃PO₄-PTFE exhibited a peak power density of 2.7 mW/cm² at 0.3 V in ambient temperature.
Solid oxide proton conductors based on yttrium doped BaZrO₃ were investigated by introducing potassium or lanthanum at the A-sites. The materials were prepared by different methods and were obtained as a single phase with space group Pm-3m (221). The unit cell of these samples is slightly smaller than the undoped one. The upper limit of solid solution formation on the A-sites for potassium is between 5 ~ 10% as introducing more K results in the occurrence of a second phase or impurities such as YSZ (yttrium stabilized zirconium). K doped Barium zirconates showed an improved water uptake capability even with 5% K doping, whereas for La doped ones, water uptake is strongly dependent on particle size and synthetic history. The conductivity of K doped BaZrO₃ was improved by a factor of two (2×10⁻³ S/cm) at 600°C compared with undoped material. Fuel cells based on Pt/Ba₀.₉₅K₀.₀₅Zr₀.₈₅Y₀.₁₁Zn₀.₀₄O[subscript(3-δ)]/Pt under humidified 5% H₂/air conditions gave a maximum power density 7.7 mWcm⁻² at 718°C and an interfacial resistance 4 Ωcm⁻². While for La doped samples, the conductivity was comparable with undoped ones; the benefits of introducing lanthanum at A-sites may not be so obvious as deficiency of barium is one factor that leads to the diminishing conductivity
The concept of peace in the Tao Te Ching
No full textThis thesis represents a first attempt to analyze Lao Tzu's main method of resolving the social and political problems in Ch'un Ch'iu and Warring States Periods. Lao Tzu, the founder of Taoism, suggested many solutions that could bring an end to the conflicts and to the ending of the disunity of China. Examples of these include the reform or abolishment of some ancient Chinese institutions as well as new principles for the enhancement and preservation of life. All these ideas were to become crystallised in Tao Te Ch'ing, which became an important religious text. In particular, the aspect of Lao Tzu's methods for solving the social and political problems of China in the Warring States Period needs more attention. In each chapter of the Tao Te Ch'ing there was a main emphasis on peace as the main method of developing social cohesion and as a cure to all fundamental human problems. Therefore, Lao Tzu's ideas about peace and his methods of solving the problems of the Warring States period are significant and from the main focus of the thesis
Tao Xingzhi ge qu. I
No full textSide A. 1. 捧著一顆心來不帶半根草去(一)(二) ; 2. 在我的世界里小孩青年最大 ; 3. 一群小好漢(一)(二) ; 4. 追悼慈母歌 ; 5. 梅香苦 ; 6. 三代 ; 7. 朝陽歌 ; 8. 小庄晓 ; 9. 问江 ; 10. 诗的学校 ; 11. 紀念牛頓与伽利略 ; 12. 拉車 ; 13. 马克思颂 ; 14. 跟青年學 ; 15. 歌唱现代 ; 16. 寂寞 ; 17. 爱国歌 ; 18. 科学的春天 ; 19. 小小徽机真灵巧 ; 20. 玩科学把戏真有趣 ; 21. 水姑娘午曲 -- Side B. 1. 大哉陶子 ; 2. 哭陶先生 ; 3. 我是中国人 ; 4. 國民與我 ; 5. 人民教师我爱你 ; 6. 我们的青春常在 ; 7. 千教万教教人求真, 千学万学学做真人 ; 8. 我要看看世界 ; 9. 今天 ; 10. 少年 ; 11. 我的小怀抱 ; 12. 看荷花舞 ; 13. 人的体操 ; 14. 问到底 ; 15. 立大志, 求大智, 做大事 ; 16. 团结御侮文体 ; 17. 民之所好三首 ; 18. 诗人节祝词 ; 19. 只道早还乡 ; 20. 好了歌 ; 21. 中国小孩子过新年 ; 22. 教师歌 ; 23. 忠心之歌 ; 24. 我爱有趣的谈天会 (未录完).陶城曲 ; 陶城演唱 ; 杜鳴心, 陳貽鑫, 巫漪丽鋼琴演奏.Possibly reproduced from other commercial recording or radio broadcast (Pending for review)"如蘭, 學鐄教授惠存: 陶城, 陳樹新贈, 1988.8.26"--Side A.Electronic reproduction from Rulan Chao Pian Audio Cassette Collection.Composer : 陶城.Singer : 陶城 ; Piano : 杜鳴心, 陳貽鑫, 巫漪丽.Sung in Chinese.Tao Cheng qu ; Tao Cheng yan chang ; Du Mingxin, Chen Yixin, Wu Yili gang qin yan zou."Rulan, Xuehuang jiao shou hui cun: Tao Cheng, Chen Shuxin zeng, 1988.8.26"--Side A.Composer, Tao Cheng.Singer: Tao Cheng ; Piano: Du Mingxin, Chen Yixin, Wu Yili.Detailed contents in vernacular field only
Benzofuran Derivatives Activators of the Chaperone Protein Hsp90: Synthesis, Interaction Studies and Biological Effects
No full textWe have recently reported that allosteric modulation of the chaperone protein Hsp901 can be achieved in an allosteric fashion using a family of 2-phenyl-benzofuran derivatives that target an allosteric pocket at the C-terminal domain of the protein.2,3 These ligands are mainly activators of the chaperone ATPase activity3 and are accelerators of the protein internal dynamics.4 As a result, they tune Hsp90 chaperone activity in ways that we are just beginning to unravel.
We are going to present the synthetic approaches towards an expanded library of about 40 benzofuran derivatives diversified at positions R1 and R2 along with the interaction studies with full length Hsp905 and the effects on Hsp90 enzymatic and chaperoning activity.
Figure 1: 2-phenyl-benzofuran diversification at positions R1 and R2 (top) and docked complex of Hsc82 (Hsp90 yeast form) with one of our derivatives (bottom).
1. Jackson, S. E. In Molecular Chaperones; Jackson, S., Ed.; Springer Berlin Heidelberg: 2013; Vol. 328, p 155.
2. Morelli, L.; Bernardi, A.; Sattin, S. Carbohydr Res 2014, 390C, 33.
3. Sattin, S.; Tao, J.; Vettoretti, G.; Moroni, E.; Pennati, M.; Lopergolo, A.; Morelli, L.; Bugatti, A.; Zuehlke, A.; Moses, M.; Prince, T.; Kijima, T.; Beebe, K.; Rusnati, M.; Neckers, L.; Zaffaroni, N.; Agard, D. A.; Bernardi, A.; Colombo, G. Chem. Eur. J. 2015, 21, 13598.
4. Vettoretti, G.; Moroni, E.; Sattin, S.; Tao, J.; Agard, D. A.; Bernardi, A.; Colombo, G. Sci Rep 2016, 6, 23830.
5. Sattin, S.; Panza, M.; Vasile, F.; Berni, F.; Goti, G.; Tao, J.; Moroni, E.; Agard, D.; Colombo, G.; Bernardi, A. Eur. J. Org. Chem. 2016, DOI: 10.1002/ejoc.201600420
Synthesis and characterization of Hsp90 allosteric activators
No full textHsp90 is a molecular chaperone playing a pivotal role in the cell life cycle1 and an established anti-apoptotic target in cancer therapy.2 The protein internal dynamics are regulated by ATP and are critical for its function. We have recently demonstrated that Hsp90 can be modulated in an allosteric fashion, targeting the protein C-terminal domain (CTD) with a family of 2-phenyl-benzofuran derivatives.3-5 These molecules increase Hsp90 ATPase rate and accelerate its internal dynamics. As a result they tune its chaperone activity in ways that we are just beginning to unravel.
The synthetic approaches towards an expanded library of about 40 benzofuran derivatives diversified at positions R1 and R2 (Figure 1) will be presented together with the interaction studies with full length Hsp90.6
Figure 1: 2-phenyl-benzofuran diversification at positions R1 and R2.
1) Jackson, S. E. In Molecular Chaperones; Jackson, S., Ed.; Springer Berlin Heidelberg: 2013; Vol. 328, p 155-240.
2) Trepel, J.; Mollapour, M.; Giaccone, G. and Neckers, L., Nat Rev Cancer 2010, 10, 537-549.
3) Morelli, L.; Bernardi, A. and Sattin, S.*, Carbohydr. Res. 2014, 390, 33-41.
4) Sattin, S. et al Chem. Eur. J. 2015, 21, 13598-13608.
5) Vettoretti, G; Moroni, E.; Sattin, S.; Tao, J.; Agard, D. A.;. Bernardi, A. and Colombo, G. Sci Rep 2016, 6, 23830.
6) Sattin, S.*; Panza, M.; Vasile, F.; Berni, F.; Goti, G.; Tao, J.; Moroni, E.; Agard, D.; Colombo, G. and Bernardi, A. Eur. J.Org. Chem. 2016 DOI: 10.1002/ejoc.201600420
Influence of allosteric Hsp90 ATPase activators on its chaperoning activity
No full textHsp90 is a molecular chaperone with a starring role in the cell life cycle1 and an established anti-apoptotic target in cancer therapy.2 The protein internal dynamics are regulated by ATP and are critical for its function. Hsp90 can be modulated in an allosteric fashion as we have recently demonstrated, targeting the protein C-terminal domain (CTD) with a family of 2-phenyl-benzofuran derivatives.3-5 These compounds accelerate Hsp90 internal dynamics and increase its enzymatic ATPase activity. As a result, they tune its chaperone activity in ways that we are just beginning to unravel.
The synthetic approaches towards an expanded library of about 40 benzofuran derivatives will be presented. The interaction studies with full length Hsp90,6 and the effects on Hsp90 enzymatic and chaperoning activity will be reported for selected compounds.
References
1. S. E. Jackson In Molecular Chaperones; Jackson, S., Ed.; Springer Berlin Heidelberg (2013) Vol. 328, p 155-240.
2. J. Trepel, M. Mollapour, G. Giaccone, and L. Neckers Nat Rev Cancer (2010), 10, 537-549.
3. L. Morelli, A. Bernardi and S. Sattin, Carbohydr. Res. (2014), 390, 33-41.
4. S. Sattin et al Chem. Eur. J. (2015), 21, 13598-13608.
5. G. Vettoretti, E. Moroni, S. Sattin, J. Tao, D.A. Agard, A. Bernardi and G. Colombo Sci Rep (2016), 6, 23830.
6. S. Sattin, M. Panza, F. Vasile, F. Berni, G. Goti, J. Tao, E. Moroni, D.A. Agard, G. Colombo and A. Bernardi
Eur. J.Org. Chem. (2016) DOI: 10.1002/ejoc.201600420
Beyond interfaces: A usability study of Chinese journal databases
No full textA presentation at the Council on East Asian Libraries (CEAL) annual meeting in Boston, MA on March 21, 2007
Rose Galaida and the Central China Relief Records, 1946: Discovery, Investigation, and Implications
No full textThe materials in the Central China Relief Records (CCRR) collection provide a window to the experiences of Rose Galaida in Hubei. The collection consists of about 100 documents totaling over 300 pages (excluding duplicate copies) and 5 photographs.Peer reviewedPublished in the Journal of East Asian Libraries and available from the journal at: https://scholarsarchive.byu.edu/jeal/vol2011/iss153/
The Tao of Miyazaki
No full textThrough this investigation into the anime films of Hayao Miyazaki, the author uses the methodologies of hermeneutics and hermeneutical phenomenology to discover just what it is that audiences around the world find so captivating about these movies. She analyzes the characters, their shadow sides, and their portrayal of archetypes according to Jungian psychology. She also studies the settings, plots, and themes of these films, and evaluates the artwork. Throughout this research into Miyazaki's anime, the author looks for levels of meaning regarding social, psychological, ecological, spiritual, and moral issues, and searches for patterns and themes that express universal essences. The patterns and principles she discovers fit into that Eastern concept of spirituality known as the Tao, a holistic and universal phenomenon that is understood as the source of everything, a philosophy of living, and a "Way" or path to enlightenment (Jung, 1997, Watts, 1993). The author presents nine of Miyazaki's films and compares each with an aspect of the Tao. Through these films, she explores the Tao principles of P'uh or simplicity; Li, our relationship with nature; Wu Wei, sensitivity to circumstances; Te, moral integrity and virtuous action; and the Yin-Yang Polarity or harmony. The author also compares Miyazaki's movie-making methods with these principles, establishing a connection between his films and his techniques, and making the argument that Miyazaki is a Tao master
Breaking New Ground in East Asia Library History
No full textReview of Peter X. Zhou. Collecting Asia: East Asian Libraries in North America (2010).Published in H-Net Reviews in the Humanities and Social Sciences and available at: http://www.h-net.org/reviews/showrev.php?id=32231March 201
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