Top PDF Thermoelectric Skutterudites: Why and How High zT Can Be Achieved

Thermoelectric Skutterudites: Why and How High zT Can Be Achieved

Thermoelectric Skutterudites: Why and How High zT Can Be Achieved

From the equation for we can see that the lattice thermal conductivity is the only parameter that allows independent tuning. Nano-structuring, as a means of bringing in nano- scale features to effectively scatter phonon prorogation thus reduce lattice thermal conductivity, has been applied in a lot of systems to improve thermoelectric properties. One mechanism is reducing the grain size to nano-scale. The introduced large density of grain boundaries leads to enhanced grain boundary scattering. This is easily realized by ball milling. Another mechanism is to introduce nano-scale foreign phases. Many efforts have been tried such as by adding more electron conductive nanoparticles or introducing filler oxides by deliberate exposure to oxygen 109 . The kinetics of these foreign phases, however, is hard to control. Here we introduce another method of nano-structuring, which is precipitation of nano-scale secondary phases according to temperature dependent filler solubility based on phase diagrams. As we have shown in Chapter 5, the solubility limit of filler atoms R in CoSb 3 system is not a single value but rather has a large dependence on the
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The Effect of Severe Plastic Deformation on Thermoelectric Performance of Skutterudites, Half Heuslers and Bi Tellurides

The Effect of Severe Plastic Deformation on Thermoelectric Performance of Skutterudites, Half Heuslers and Bi Tellurides

This article is to show that SPD-processing of thermo- electrics can provide values of figure of merit (ZT) higher than 1.2, and thus gets highly attractive for materials which enable sustainable generation of electric power. These high values arise from the ultrafine grained microstructure in combination with a high level of point, linear and surface lattice defects which significantly enhances the scattering of the phonons, thus leading to a minimum of thermal conductivity and therefore to exceptional values of ZT. The extent of SPD-induced enhancement depends on the special thermoelectric materials. So far, the following thermo- electrics have been tried to get improved by SPD processing: (1) From all thermoelectrics, n- and p-type skutterudites benefit most from SPD-processing especially if one applies high pressure torsion (HPT) to already hot-
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Thermoelectric Properties of Group 13 Elements Triple Filled Skutterudites: Nominal InxGa0 02Tl0 20Co4Sb12

Thermoelectric Properties of Group 13 Elements Triple Filled Skutterudites: Nominal InxGa0 02Tl0 20Co4Sb12

reflects the efficiency of the energy conversion, the develop- ment of high-ZT materials has a significant meaning for more effective energy savings by recycling the waste heat. To achieve high ZT, a large S, low µ, and low ¬ are required, however, S, µ, and ¬ el are strongly interrelated with each other

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How is the balance between protein synthesis and degradation achieved?

How is the balance between protein synthesis and degradation achieved?

This reflects a primary causal discernment. As a general matter, chemical events are bal- anced by mass action among their constituents, and despite the unique circumstances of protein synthesis and degradation, physical law does not allow an exception to this rule; it provides no other means of achieving balance. The question then is not whether this occurs, but how and where? If balance is not achieved within the synthetic and degrada- tive reaction sequences in their own right, and it is not, then it must take place external to them. That is, the mass action event must occur somewhere in time and space between the manufacture of proteins on ribosomes and their breakdown in protea- somes, in other words in the solvent phases of the cell that contain both of these structures 5 .
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How To Understand Why Doctoral Student Attrition Is High In The United States

How To Understand Why Doctoral Student Attrition Is High In The United States

surveyed all of these individuals and gave them six specific options from which to choose from, none of which had anything to do with issues related to the program or institution. In both Lovitts’ (2001) and Berelson’s (1960) studies, then, faculty and administrators’ attributions for doctoral student departure fell entirely on the shoulders of the students who left, rather than attributing any responsibility to the program or institution. In other words, while a lack of financial resources was high on the list of reasons for student departure in Berelson’s study, it was not that the institution was responsible for securing more funding on behalf of students but rather that funding simply did not exist. While Lovitts also spoke with departed students and learned of their actual reasons for departure, neither study spoke with currently enrolled students to determine their attributions of student departure within their programs. Moreover, both of these studies were conducted with individuals recalling past events in relation to attrition, with Berelson’s study conducted in the late 1950s and Lovitts’ study conducted with individuals who had been in a 1982–1984 cohort. The perspective of current students and their beliefs about student departure within their spe- cific departments may lead to a better understanding of why doctoral student attrition occurs, particularly as current students are those who may be considering attrition within the present context. Furthermore, as both studies were conducted with students who were in graduate school more than two decades ago, information gleaned from these studies may not be as relevant today. Therefore, combining current students’ impressions of doctoral student attrition along with faculty members’ impressions on this topic, a more holistic picture of student attrition in doctoral programs may begin to form.
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Generic but Expensive: Why Prices Can Remain High for Off-Patent Drugs

Generic but Expensive: Why Prices Can Remain High for Off-Patent Drugs

“[N[ot going to simply ramp up the production lines to accommodate new demand, if it means that the drugs will be imported into the U.S. to skirt their tiered pricing. Nor will the foreign countries allow their local supply to be skimmed off, only to create local shortages of important medicines.” Arlene Weintraub, FDA to Consider Drug Importation in Battle Against High Drug Prices, F ORBES (July 19, 2018, 10:18 AM), https://www.forbes.com/sites/arleneweintraub/2018/07/19/fda-to-consider-drug- importation-in-battle-against-high-drug-prices/ (internal quotation marks omitted) (quoting Dr. Scott Gottlieb). 165. Jonathon Gatehouse, Canada’s Population Tops 37 Million After Record Two-Year Surge, CBC N EWS (June 14, 2018, 2:15 PM), https://www.cbc.ca/news/thenational/national-today-newsletter-trrump-sued- canada-population-1.4700759.
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Simple but effective LIS research: why we need it, and how we can do it

Simple but effective LIS research: why we need it, and how we can do it

At this point we should ask questions of referees and editors. In the past I have done this. After reading a particularly unconvincing journal article purporting to be based on a survey of unspecified numbers of Nigerian women I wrote to the editor of the journal concerned. I asked how he justified publishing an article that offered no convincing evidence, in the form of the questionnaire itself, an account of the target and responding populations and some convincing detail on results, that its survey had actually taken place. My letter received no reply. One sympathises to an extent. Even the best LIS journals experience times when suitable articles are too few in number and poorer journals must be desperate for copy most of the time. This is, however, no excuse for publishing dangerous trash. The expected standards of research in a discipline are defined in various ways. Conference presentations, and even semi-published reports might be seen as works in progress, needing to respond to less demanding standards, but the journal article should truly define what the discipline expects. At present it seems that it expects questionnaire surveys and isn’t too concerned how suitable and
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WHY AND HOW TO REVISE

WHY AND HOW TO REVISE

own paper. This is why getting a second reader is the smartest thing you can do as a writer. A second reader can do a lot for you: she can tell you where she got bored, or confused, or offended, and she can give you advice for improving your work. Remember, though: when you ask someone to read your work, you should be prepared for any criticism they might make. Don't be defensive; instead, try to figure out why your reader feels as she does about your paper. Of course, you don't have to follow every suggestion that your reader makes, but you will certainly profit from her comments and questions, even if you do decide to ignore her advice in the end.  Be a second reader. There's no better way to learn how to revise your paper than to help someone else revise his. You'll find that your critical eye works much better when it's focused on your friend's paper than it does when it's focused on your own. You can be more objective when looking at someone else's work. You can see more easily what's gone wrong in a paper and how to fix it. When you practice these skills on someone else's paper, you become more adept at practicing them on your own.  Visit the OWRC. Technically, this falls in the category of "getting a second reader."
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Low Contamination Rates in Bag Urine Samples Can Be Achieved

Low Contamination Rates in Bag Urine Samples Can Be Achieved

current evidence on diagnostic performance of urine sampling with this technique was sparse and that further research was needed on this topic. In a condition of high pretest probability of UTI (i.e.: positive nitrite test), a positive culture obtained by BUS could be accepted as a reliable result [9]. In a direct comparison between BUS and CS, Etoubleau and co. [4] found that bag specimens led to unreliable results in 40% of cases versus 5.7% of CS. They suggested that CS should be used to confirm a BUS-obtained positive result, but that systematic catheterization for every child suspected to have UTI could not be recommended.
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Climate-change policy: why has so little been achieved?

Climate-change policy: why has so little been achieved?

But even if the underlying assumptions were soundly grounded, and supported by empirical evidence, the derived supply function is essentially restricted to the ‘optimal’ costs of the technologies, and takes no account of the fluctuations in the costs of the technologies as market conditions vary, and assumes that the policy framework will lead to their costless deployment. It is the (least) costs of the equipment, not the cost of producing the outputs. Neither turns out to be well-founded. A rapid least-cost roll-out of low-carbon technologies assumes that the manufacturing capability anticipates demand, and hence prices do not reflect imbalances between demand and supply. They are always in equilibrium. The evidence is to the contrary: for example, the prices of wind turbines have risen sharply as the dash-for-wind has been embedded in renewables policy; and now there is evidence in the sharply rising prices of new nuclear development technologies as manufacturing production lags demand. These price effects are of a significant order of magnitude—rendering the cost numbers in the Stern Report all but useless for the purposes of public policy design and implementation. The technology costs assume that the energy systems are optimally designed to facilitate their deployment. No account is taken in the Stern Report of the costs of system-wide changes to the transmission and distribution, for example, and, in the case of wind, the assumptions about availability and back-up supplies are optimistic. While these may not matter at the margin, with large-scale deployment of these technologies, they are likely to be significant. Given the scale of the switch from high- to low-carbon technologies implied by the overarching targets, non-marginal deployment should be taken into account. 22
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PALESTINIAN REFUGEES HOW CAN A DURABLE SOLUTION BE ACHIEVED? CEPS Middle East Working Paper No  6, July 2003

PALESTINIAN REFUGEES-HOW CAN A DURABLE SOLUTION BE ACHIEVED? CEPS Middle East Working Paper No. 6, July 2003

The Madrid Conference was convened in October 1991 on the basis of UNSC Resolutions 242 and 338. 21 Even though formally the Palestinians were part of the Jordanian delegation, by November 1992, the PLO became de facto recognised as the representative of the Palestinians for the purpose of the negotiations later on. 22 The multilateral track of the peace process was launched in January 1992, to lay the foundations for securing the peace that might come through bilateral talks by initiating efforts at “cooperation on arms control and regional security, the environment, water resources, and regional economic cooperation and development.” Only when the Palestinians threatened to boycott these talks did the Americans agree to launch a fifth set of multilaterals to deal with refugees. This is how the Refugee Working Group (RWG), headed by Canada, was formed. 23
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Can universal access be achieved in a voluntary private health insurance market?

Can universal access be achieved in a voluntary private health insurance market?

Given that premium differentiation was not fully feasible and politically unat- tractive, the only possible way commercial health insurers saw to avoid a premium death spiral was to attract low-risk individuals by introducing new insurance policies with high deductibles. At the start of the 1970s, the post-war baby-boom generation was coming of age, and the commercial insurers expected to attract a high number of new low-risk customers by these high deductible plans. This strategy, however, backfired. High deductible policies were soon copied by most other health insurers, with the notable exception of most insurance foundations because deductibles, co-payments and risk-rating were deemed incompatible with the solidarity principles they adhered to. Several small mutual not-for-profit insurers, however, stole a march on commercial insurers. Because of their small and young portfolios, they could match any premium discount offered by com- mercial insurers and still be more generous. Contrary to commercial insurers who still used agents to sell insurance products, the mutual health insurers had discovered the benefits of direct-writing and had started aggressive marketing campaigns to attract new subscribers (Schut, 1995; Vonk, 2013).
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Critique of Axiological Reason: Why the Idea of Values has Achieved the Totality in Modern Culture

Critique of Axiological Reason: Why the Idea of Values has Achieved the Totality in Modern Culture

The attitude to Values in the modern philosophy, basically, has little or no difference from the times of ancient Greece or Middle Ages. The essential commonness of the philosophical thinking of these two, though very different, epochs lies in the fact that the first one does not exist within the subject- object paradigm, and the second one moves beyond it, asking who comes after the subject? [14]. Meanwhile, Values represent manifestations of human subjectivity (this is declared by axiology itself) and borders of the value-based attitude to the world go right along its “remains”. The thing that can be named as “the modern philosophy” (meaning “the epoch embraced in the notion”) has evolved from inavailability to continue thinking of a human language and technology (two poles that constitute culture) as a “mixture” of subjective and objective things. “A question about the technology”, as it is set by modern thinkers 7 , and “a linguistic turn” determine the main circle of interests and the trend of the modern philosophical thought. All significant theories think that Values have been derived from something else, and it means that they are inexplicable out of themselves. Followers of Marks deduce them from the class position of the subject; psychoanalysis looks at them in a symptomatic manner as manifestation of unconscious attitudes and/or symbolist order; hermeneutics and analytical philosophy think of them as the things derived from the usage of the language; classical phenomenology finds a special place for them in the structure of consciousness; fundamental ontology looks at them through the phenomenon of throwness; postmodernism sees in them, mainly, simulacra. It is not surprising that the modern philosophy has formed a rather critical attitude and unusual professional consensus concerning the place that is taken by Values in the life of a person, culture, and society. For more details, please, see [15]. This topic can be broadened, but it is thought that within this context it is sufficient to point at the state of facts, namely to indicate that the modern philosophy does not consider Values to be the fundamental foundation of the Being of a person and culture.
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Getting Real How High-Achieving Women Can Lead Authentically

Getting Real How High-Achieving Women Can Lead Authentically

One of the most interesting observations from CCL’s re- search is that it is possible to be authentic in one aspect of your life and not in another. For instance, a person who has a job that is aligned with her values might feel she can’t behave fully like herself in her relationships outside of work. One young executive was in an authen- tic situation at work but had a growing resentment of her new husband. He was dissatisfied with his job and wanted to find a new position in a different area of the country. She felt bound by tradition to say she would go with him, but at a deeper level she was having difficulty adjusting from a “me” to a “we” framework and learning how to make major decisions as part of a couple. She kept finding ways to block the move.
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Atlas Copco. Oil-free rotary screw compressors. ZR/ZT FF & ZR/ZT VSD-FF kw/ hp

Atlas Copco. Oil-free rotary screw compressors. ZR/ZT FF & ZR/ZT VSD-FF kw/ hp

Only oil-free compressors deliver oil-free air. Whether your activities are in pharmaceutical production, food processing, criti- cal electronics or a similarly exacting industry, it is essential to eliminate risk. That’s why you need an Atlas Copco risk-free so- lution: oil-free screw compressors especially for applications de- manding the highest levels of purity. Zero oil means zero risk. Zero risk of contamination. Zero risk of damaged or unsafe products. Zero risk of losses from operational downtime. Above all, zero oil means zero risk of ruining your hard-won reputation.

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Why is Zika virus so rarely detected during outbreaks and how can detection be improved?

Why is Zika virus so rarely detected during outbreaks and how can detection be improved?

dispersal, often spending their entire lives in the room where they emerged [28]. An entomological investiga- tion in randomly selected houses failed to detect ZIKV in mosquito in Yap [21], while positive pools were detected when mosquito were collected in and around clinically ill patient households [10–12]. During outbreak inves- tigations, households of Zika patients are identified via the addresses or phone numbers found in medical regis- ters or patient identification forms sent by physicians to the laboratory along with samples for diagnosis. How- ever, only around 20% of these ZIKV infected people are symptomatic [2], and an even smaller fraction seek medical care and thus may be identified and investigated through this system. Moreover, in many cases basic loca- tion information (exact address and phone number) are not reported in medical documents. Thus, it is impos- sible to identify and investigate the majority of house- holds in which a ZIKV-infected individual lives. Further, it is not certain that a given patient was infected in his/ her own household because infections could have been contracted in other neighborhoods or villages during the course of normal movements. To alleviate this problem, medical personnel must be instructed to clearly record the address, phone number and travel history in each patient identification form.
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Why Digital Copyright Can Succeed.

Why Digital Copyright Can Succeed.

http://www.kreber.com/c indigo.html.as of22 March 1998. Bookstores are not yet among their suggested uses for their product.. bookstore employees would end up with copies of the digita[r]

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Why Johnny Can t Encrypt

Why Johnny Can t Encrypt

user interface is evaluated against a specific list of high-priority usability principles; our list of principles is comprised by our definition of usability for security (in the section “Defining Usability for Security”) and its restatement specifically for PGP (in the section “A Usability Standard for PGP”). Heuristic evaluation is ideally performed by people who are “double experts,” highly familiar both with the application domain and with usability techniques and requirements (including an understanding of the skills, mindset, and background of the people who are expected to use the software). Our evaluation draws on our experience as security researchers and on additional background in training and tutoring novice computer users, as well as in theater, anthropology, and psychology. Some of the same properties that make the design of usable security a difficult and specialized problem also make testing the usability of security a challenging task. To conduct a user test, we must ask the participants to use the software to perform some task that will include the use of the security. If, however, we prompt them to perform a security task directly, when in real life they might have had no awareness of that task, then we have failed to test whether the software is designed well enough to give them that awareness when they need it. Furthermore, to test whether they are able to figure out how to use the security when they want it, we must make sure that the test scenario gives them some secret that they consider worth protecting, comparable to the value we expect them to place on their own secrets in the real world. Designing tests that take these requirements adequately into account is something that must be done carefully, and with the exception of some work on testing the effectiveness of warning labels, 16 we
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Structure, Annotation and Tools in the Basque ZT Corpus

Structure, Annotation and Tools in the Basque ZT Corpus

The ZT corpus (Basque Corpus of Science and Technology) is a tagged collection of specialized texts in Basque, which wants to be a main resource in research and development about written technical Basque: terminology, syntax and style. It will be the first written corpus in Basque which will be distributed by ELDA (at the end of 2006) and it wants to be a methodological and functional reference for new projects in the future (i.e. a national corpus for Basque). We also present the technology and the tools to build this Corpus. These tools, Corpusgile and Eulia, provide a flexible and extensible infrastructure for creating, visualizing and managing corpora and for consulting, visualizing and modifying annotations generated by linguistic tools.
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Long term follow up of high risk children: who, why and how?

Long term follow up of high risk children: who, why and how?

vi. Motor skills – the properties of various infant motor scales have been recently reviewed [33], including Prechtl’ s General Movements Assessments [34], the Alberta Infant Motor Scale (AIMS) [35], the Test of Infant Motor Performance (TIMP) [36], the Neuro-Sensory Motor Development Assessment (NSMDA) [37] and the motor scales of Bayley Scales of Infant and Toddler Development [38]. Abnormalities of Prechtl’s General Movements Assessments in the first months of life, particularly the absence of normal fidgety movements by 3 months of age, can be predictive of the later development of cerebral palsy in high-risk children, whilst the TIMP is able to identify motor delay from 32 weeks’ gestation up until 4 months’ corrected age [39]. The AIMS, NSMDA and Bayley can be used from 1 month but are less useful at the bottom end of their validated age ranges, and are better from 4 months onwards. Whilst these tools can be useful in identifying children at risk of motor impairments, including cerebral palsy, false positives and negatives are common and ongoing follow-up is recommended [40,41]. In older children standardised motor assessments are applicable if there is a concern about motor performance. From three years of age fine and gross motor function can be assessed with the Movement Assessment Battery for Children-Second Edition [42], or the Bruininks-Oseretsky Test of Motor Proficiency, Second Edition (BOT-2), either screener or full version [43].
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