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The article discusses the popularity of English as a second language (ESL) course in non-English countries and it presents online resources that are helpful to teachers working abroad. Some of Web sites presented are "Teaching Professor Newsletter" at http://www.MagnaPubs.com, "Teaching English" at http://www.TeachingEnglishGuide.com, and "ESL and Bilingual Program Models" at http://www.cal.org/resources/digest/rennie01.html. According to the author, the resources serve as a starting point for educators in teaching English abroad as well as tools to become more effective in their work.

The article features podcasting, a term synonymous with downloadable radio-style Internet audio programs that are uploaded automatically to computer. The term podcasting is a combination of Apple's iPod and the word broadcasting. It is compared to a magazine subscription in a way that a one needs to register for subscription first, retrieve from the aggregator and download using iTunes. However if one decides to delete what has been downloaded, try using the Yeast Radio. Lastly, subscription can be cancelled any time.

The article provides information about the Internet resources related to multicultural learning. Two useful sites for software programs to learn the language or simply to look up a phrase in a language dictionary are ZDNet Downloads and C/Net Downloads. In doing a search on the general term "language," a researcher will get dozens of false hits because of computer programming languages, so be selective and use specific terms like "Spanish language," "French language," and so on. Linguistic microcomputers can be used as dictionaries and they also have the capability of text translation, e-mailing, faxing, and digital voice recording as well; they also include a grammar book. They recognize multilingual speech and have touchsensitive displays.

The article focuses on softwares and Web sites for electronic books. An e-book or electronic book is a digital book that can be read on a handheld personal display assistant (PDA) or a computer. E-books are usually purchased online and are downloadable. E-books are read on an e-book reader, which is proprietary software that emulates the book format. Most e-book software vendors use a form of Open eBook (OeB) based on the principles similar to HTML and XML computer languages, used to create Web pages. In the OeB format displays can be scaled to various screen sizes. Many libraries are beginning to purchase e-books because they can be accessed online from anywhere. A few specific handheld personal display readers that make good e-book readers include Palm, Handspring, Casio Cassiopeia, Compaq iPAQ and Hewlett-Packard Jornada or Psion. Because they boast more than 20 million users, PDAS have reading software available despite their small screens and average resolution. RCA Gemstar manufactures a couple of dedicated e-book devices with larger screens and better resolution than PDAS.

This article reports that the racial identification occurs almost on a daily basis by employers. In society racial identification is tied to things such as the awarding of government contracts and admission to colleges and universities. Such affirmative action measures have been necessary in order to counteract past discrimination and give minorities a fair and equitable chance at improving their status in society. Some persons contend that there is good racial profiling and bad racial profiling. The author is not convinced that racial profiling in any context is a positive thing. He does however, realize that it exists for a variety of reasons. An aftermath of the bombing of the World Trade Center and the Pentagon has been the attempt to suspend the rights of noncitizens in the U.S. Since there are a few who might be involved in terrorism, John Ashcroft, attorney general of the U.S., has asked Congress to enact new counterterrorist laws. The new laws allow noncitizens to be held for indefinite periods of time and to be subject to surveillance that is broad in nature.

This article offers information on the Hispanic American Periodicals Index. It covers information about Central and South America, Mexico, the Caribbean Basin, the U.S.-Mexico border region, and Hispanics in the U.S. It contains a complete bibliographic citations to articles, book reviews, documents, original literary works, and other materials appearing in more than 400 key social science and humanities journals published worldwide. The index is devoted primarily to Latin American studies. Its focus is mainly on the social sciences and humanities, but it includes a sizeable portion of material on Hispanic American Studies. There is little, if any, coverage of science. Literary subjects receive a great deal of attention. The index also includes significant citations on politics and government, public administration, foreign relations, commerce and trade, banking and finance, business and industry, economic development and policy issues, economic integration, social movements, indigenous affairs, gender studies, environmental issues and the drug trade. Other key subject areas include history, geography, archaeology, anthropology, ethnography, folklore, religion, art, drama and film studies.

This article features electronic products that can help educators, librarians and researchers better understand diverse cultures. The software Decision, Decisions 5.10: Immigration from Tom Snyder Publications, allows students to use critical thinking skills to gather and review information, discuss options and take actions. The user plays the role of a U.S. president who is up for reelection. He and his four advisors face a real-life dilemma involving thousands of boat people from a war-torn area rapidly approaching U.S. shores. The Web-based product Discovering Multicultural America from Gale, has a comprehensive multicultural source covering four U.S. major ethnic groups, namely, African Americans, Asian Americans, Hispanic Americans and Native Americans. Omissions aside, the product is an exceptional value, particularly for historical research. The publisher promises frequent updates so that it can be a resource for the study of current events as well. The interactive educational software The African American: A Proud People With a Great Heritage exposes children to the roots of African-American culture and history. The designers are doctor James L. Jones and Merly Vance, who narrate much of the story.

This article discusses opinions regarding the recognition of English as the official language of the United States and how immigrants who enter the country must be required to learn the language. The English Language Unity Act and English law introduced by Steve King, the Republican state senator in Iowa, is also discussed. Statistics are presented from a survey conducted with members of the Democrat, Republican, and other non-affiliated parties who all favored a law to make English the official language.

The article provides information on some online resources that offers multicultural videocasting. FireAnt, a free videocast player has a limited number of multicultural offerings including "Al Jezeera: Global News," "Simply Ming," 'The French Pod Class," and Superette. The Spanish version of Yahoo, Yahoo Telemundo has three video sections. Few programs with ethnic characters or actors on American Online's Internet service called IN2TV are mentioned.

The article evaluates various products related to electronics including "World eBook Library," "World Geography: Understanding a Changing World and Little Bill Thinks Big," and "Little Bill Thinks Big."

This article reports that the everyday life of people in various cultures can be viewed up close and personal in weblogs or "blogs." These online diaries or journals can contain interesting experiences of ordinary people. Weblogs show us just how similar life can be among cultures and can give us insights into similarities and differences between cultures. Individual diarists' free expression helps us understand cultural issues and practices that each of them faces daily. Some weblogs can be addicting to read, as the reader is enticed to come back to see what happened to the diarist. In an era of reality television, weblogs offer daily or weekly updated postings, which can contain some very candid intimate details, such as details about the posters sex life or what he or she ate for breakfast. Weblogs many times contain reactions to current events. Weblogs are definitely a creative reconstruction of each blogger's life and thought. Many contain pictures, video clips, moving animation, or links to other sites for illustration.

The article focuses on the author's decision to explore multiracial web sites after attending a joint program of REFORMA: The National Association to Promote Library Services to the Spanish Speaking and EMIERT, the Ethnic and Multicultural Information Exchange Round Tables at the annual American Library Association meeting in 1999. Claudette Bennett, an employee of the U.S. Census Bureau, described the new multiracial reporting question for the 2000 census, which will show an estimated five to eight million persons of multiracial descent. Linda Absher from Sequent Computer Systems described her personal experience in a multiracial family and shared her web page. Karen Downing from the University of Michigan Library shared her web page, Karen Downing's Homepage, where she presents her interracial family and a bibliography on Resources by and about Interracial & Multi-Cultural People. At the REFORMA presentation Claudette Bennett went into great detail about the racial identification in the 2000 Census. People who marked the American Indian or Alaska Native category were asked to provide the name of their principal or enrolled tribe. People who selected the "Other Asian," "Other Pacific Islander," or "Some other race" were asked to write in their specific race or ethnicity.

The article focuses on how to create multicultural wikis. The author provides hyperlinks to free wiki software that is available on the Internet. The author provides hyperlinks to wiki search engines that give comprehensive results. Teachers have been known to construct a wiki page and instructed their students to contribute.

The article presents information on a traditional print journal that focuses on the indigenous people of California and a brand new online journal produced in Hawaii that appeals to culturally diverse youth. The name of the print journal is "News from Native California." Malcolm Margolin publishes it. Its Managing Editor is Margaret Dubin and Clapperstick Institute, a nonprofit educational corporation, owns the journal. The name of the online journal is "Urban Mozaik Magazine." The editor of the journal is Carolyn Quan. The journal titled "News from Native California" contains mostly short articles, complemented by apt photographs and illustrations. The journal seeks to be "the inside view of the California Indian World." Both historic and contemporary points of view can be found in the magazine. Each issue of the journal has approximately five articles and gives attention to the education and social events of various tribes, legal struggles and Native artists in pictures and illustrations. This journal of 15 years provides thorough knowledge with depth written from an Indian perspective and it happens to be published at a modest price.

Reviews the computer software Moorditj: Australian Indigenous Cultural Expression from Crystal Productions.

One feasible solution to reduce the cost of concentrated solar power is to employ a higher temperature and efficiency supercritical carbon dioxide Brayton power cycle. An alternative heat transfer medium and thermal energy storage (TES) system therefore needs to be explored. This work considered a variety of phase change materials (PCMs) and graphite as the storage media in four indirect shell-and-tube storage configurations, including a 3-PCM and 5-PCM cascade storage, a PCM-graphite-PCM hybrid storage and a single graphite storage. The sizing and design of the TES systems were performed by using a dynamic cycling methodology based on a transient 2D numerical model. The cost of those designs were then determined by using an economic model developed inhouse. This work also investigates the impact of some geometric parameters and cost assumptions on the techno-economic performance of the TES system. The analysis suggests a scenario exists whereby a low thermal efficiency storage system which therefore utilises less tube or storage material could be more cost-effective. Overall, the cost of hybrid TES is the lowest among all studied systems, at $26.96/kWh t and $21.49/kWh t for charging temperature of 720 °C and 750 °C, respectively, followed by the 5-PCM storage at $28.06/kWh t and $21.82/kWh t , respectively. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Designing a cost-effective phase change thermal storage system involves two challenging aspects: one is to select a suitable storage material and the other is to increase the heat transfer between the storage material and the heat transfer fluid as the performance of the system is limited by the poor thermal conductivity of the latent heat storage material. When used for storing energy in concentrated solar thermal power plants, the solar field operation temperature will determine the PCM melting temperature selection. This paper reviews concentrated solar thermal power plants that are currently operating and under construction. It also reviews phase change materials with melting temperatures above 300°C, which potentially can be used as energy storage media in these plants. In addition, various techniques employed to enhance the thermal performance of high temperature phase change thermal storage systems have been reviewed and discussed. This review aims to provide the necessary information for further research in the development of cost-effective high temperature phase change thermal storage systems. [Copyright &y& Elsevier]

Oncocytoma is an uncommon benign, typically solitary renal tumor first reported in 1942. Renal oncocytomas are rarely multiple and/or bilateral. Accurate preoperative diagnosis and differentiation from renal carcinoma is difficult. We report the radiology and pathology of a patient with bilateral renal oncocytomas and review the literature of this rare presentation. [Copyright &y& Elsevier]

Fertilizers have been given significant attention due to their critical need for agriculture yield to meet the demand for food growth arising from population growth. The demand for potassium fertilizer (metric tons of K 2 O) has increased by 12% between 2015 and 2020. Therefore, the concern about the limited availability of soluble potassium resources in the southern hemisphere has become a key research focus for identifying alternative resources and technologies. This study presents a review of the fundamental knowledge of alternative technologies, such as acid leaching, hydrothermal and molten salt technology, as well as different alternative K-bearing silicate resources (ultrapotassic syenite, nepheline syenite, glauconitic sandstone and mica). Studies on fluxing agents proposed for the extraction of K+ based on different methods were analysed and compared. This paper offers a detailed overview of experimental kinetic analysis, kinetic and mechanism reactions, aims to improve the extraction technology and address relevant industry challenges. This review also reports on thermodynamic analysis of the mineral-salt/acid/alkaline systems, providing insights into the basis of industrial applications. Finally, the review provides opportunities and challenges of each technique and has shown that further techno-economic and process analysis are required to better identify the viability of each technique for large-scale industrial demonstration. [ABSTRACT FROM AUTHOR]

A shell-and-tube design with different thermal energy storage (TES) media was investigated as a promising TES system for a next generation concentrated solar power (CSP) plant. Sensible TES using graphite, latent TES using phase change materials (PCMs) and a hybrid of both were investigated. A two-dimensional transient heat transfer model was applied to simulate the thermal performance of multiple shell-and-tube TES modules connected in series. Considering the realistic operation of the CSP plant, an intensive numerical investigation was conducted to design and size the storage system. The TES systems studied were categorized as 3-PCM cascade, 5-PCM cascade, PCM-graphite-PCM hybrid and single graphite. All the PCMs considered in this paper have been experimentally proven as potential candidate storage media. It was found that all the TES systems studied, if well designed, can meet the CSP operational requirements. In comparison, single graphite storage is less problematic, but it has the lowest storage density (47.3 kWhr/tonne). By forming a PCM-graphite-PCM sandwich configuration, the energy density was increased to 60.9 kWhr/tonne and the storage effectiveness of this hybrid system is 70.7%, the highest among all the TES systems studied. • A 2D model was validated and verified using experimental and CFD results. • Six designs of sensible, latent and sensible-latent hybrid storage were investigated. • The overall storage effectiveness of the hybrid design is the highest. • The effectiveness of the graphite system is improved by 21.2% in hybrid design. [ABSTRACT FROM AUTHOR]

Highlights • Comparison of overall exergy efficiency of different thermal energy storage systems. • Liquid sodium as HTF reduces the gap in exergy efficiency between PCM and two-tank. • High temperature sCO 2 as HTF in PCM reduces the exergy efficiency gap with two-tank. • Na with a high temperature PCM provides high storage density and exergy recovery. • Optimal temperature of PCM depends on PCM/HTF and inlet hot/cold temperatures. Abstract Different options of sensible and latent heat storage systems comprising different types of heat transfer fluids, heat storage media or phase change materials (PCMs) have been compared considering the upstream and downstream requirements of a concentrated solar power cycle. For an optimal system, analysis of both the energy efficiency and exergy recovery of the storage system and the whole cycle of heat to power is necessary. This study provides this analysis, comparing a two-tank sensible storage system to latent heat shell and tube storage system, using an analytical method, ε-NTU. For the case of molten salt as the PCM and sCO 2 as the heat transfer fluid, results show 4.02% higher exergy recovery for the two-tank system at a working temperature range 450–700 °C compared to 450–660 °C for the latent heat storage system where the upper limit is the PCM melting temperature. Compared to the Carnot cycle efficiency (the highest rate of useful energy (exergy) recovery for an isentropic process) of 70%, the overall efficiency of the two-tank system, the base case of molten salt/sCO 2 , molten salt/Na, and molten metal/sCO 2 are 57.41%, 53.39%, 55.21%, and 53.55%, respectively. The gap in efficiency between the sensible and latent heat storage systems decreases by lowering the thermal resistance of heat transfer fluid side and/or the PCM side. Specifically, the gap in efficiency decreases 45% by using liquid Na instead of sCO 2 and a 4% decrease is observed when replacing molten salt with a molten metal like aluminium as the PCM. Using PCMs with higher melting temperature is preferred with liquids with high thermal conductivity like Sodium. For a heat transfer fluid such as sCO 2 with low thermal conductivity, a higher inlet fluid temperature and/or a low temperature PCM can provide high exergy efficiency. For a specific combination of PCM and heat transfer fluid, an optimal melting temperature exists depending on the inlet temperatures during charging/discharging and the thermophysical properties of the media. The study shows that PCM storage provides opportunities to minimise causes of irreversibilities to achieve simultaneous high volumetric energy density and high exergy recovery for CSP application in comparison with the conventional two-tank sensible storage. [ABSTRACT FROM AUTHOR]

Abstract In the current study the feasibility of using solar-based renewables coupled with thermal energy storage (TES) to displace gas for heating was explored. To assess the feasibility, a numerical model of an air-based encapsulated phase change (EPCM) storage system was developed, validated, optimised, and economically costed. The optimised air-based EPCM system utilised a high and low melting temperature phase change material (PCM) with a sensible storage filler. It was found that a capsule radius of 10 mm and PCM volume of 13% resulted in the lowest cost of discharged thermal energy of $25.55/kWh when storage effectiveness and pumping power was considered. This system was then coupled to solar data for Adelaide, South Australia, to simulate the performance of a 1 MWt heat load over a year. By solving an hourly system generation and demand profile, it was found that a concentrated solar thermal (CST) and photovoltaic (PV) system coupled with TES was able to economically reduce gas consumption by 45–65% when the price of gas was $30/GJ. By employing near-term cost estimates for CST and PV systems coupled with TES, it was found that gas consumption could be reduced by similar amounts with a gas price of $20/GJ. Highlights • Solar-based renewables coupled with TES is explored to reduce commercial/industrial reliance on gas as a heat source. • A numerical model of an air-based EPCM system is developed, validated, optimised, and economically costed. • A 2-PCM hybrid system was found to produce the desired performance at the lowest cost ($25.55/kWh t). • Both PV and CST systems are able to currently compete with gas as a heat source when the gas price is more than $25/GJ. • Predicted cost reductions coupled with low cost grid electricity show these systems capable of being economic at $15/GJ. [ABSTRACT FROM AUTHOR]

Highlights • Na and Li sulfates solid-solid PCM mixtures are proposed for cascade systems. • The thermal stability, specific heat capacity and latent heat are obtained. • NaLiSO 4 is the most stable material with lower cost. • NaSO 4 shows irreversible phase transition. • A selected mixture of LiSO 4 and NaLiSO 4 shows $50.2 kWh th −1. Abstract In this work, we investigate novel solid–solid phase-change cascade systems based on mixtures of lithium and sodium sulfates. Solid–solid phase-change materials (PCMs) can be coupled with concentrated solar power technologies. They present several advantages over solid–liquid PCMs including lower thermal expansion, lower or no corrosiveness, and no need for encapsulation. In solid–solid PCMs, the energy is stored during crystal structure transitions. Specifically, lithium sulfate undergoes a crystal structure transition (monoclinic to cubic) at 576 °C, which is a suitable temperature for concentrated solar thermal technologies. Due to the high cost of lithium sulfate, we evaluated the potential of mixing lithium with sodium sulfate to create solid–solid cascaded PCM systems to provide higher thermal storage densities. We used differential scanning calorimetry, high-temperature in situ X-ray diffraction and thermogravimetric analysis to evaluate the phase-transition temperature, phase-change enthalpy, specific heat capacity, crystalline phase composition and thermal expansion. The obtained values for heat capacity and enthalpies of phase transitions showed good agreement with available thermodynamic databases. Therefore, further calculations of thermodynamic properties of each mixture in the system were performed for designing cascaded latent thermal energy storage system. From the PCM mixtures studied, NaLiSO 4 shows the greatest stability under ambient conditions. A mixture of 59.17% NaLiSO 4 and 40.83% Li 2 SO 4 allows an optimum charge of both PCMs for power cycles such as supercritical CO 2. Economic assessment revealed that this cascade system has an estimated cost of $50.2 kWh th −1. [ABSTRACT FROM AUTHOR]

Highlights • Radiant wall used as TES for a heat pump coupled to a PV array. • Deterministic control concepts were optimized for radiant wall pre-cooling. • Investment in PV panels was fully exploited only under solar control strategies. • A minimum of PV nominal power was required for optimizing solar controls. • Best solar control had lower operation cost than best peak load shifting control. Abstract Thermally activated building systems (TABS) can work as thermal energy storage (TES) systems, which are useful in shifting the energy use of space cooling and heating in buildings. The present study analyses and optimizes simple deterministic control concepts for radiant wall supplied by a heat pump for cooling purposes. First, the "solar" concept was studied, which was focused on exploiting the output of a photovoltaic (PV) array. Secondly, a "peak load shifting" concept exploiting the low electricity cost and high heat pump energy efficiency during night periods was evaluated. The results showed that the "solar" concept saved between 57% and 95% in comparison to a conventional control in different PV installed capacities. Moreover, the optimized "peak load shifting" concept had lower operation cost than the conventional control with most of the PV configurations proposed. Therefore, the study showed that the investment in the PV array was fully harnessed only with specific controls. Furthermore, the "solar" control concepts were found to help achieving the goals of net-zero energy buildings by maximising self-consumption of renewable energies in the building, as well as reducing the total imported/exported energy. [ABSTRACT FROM AUTHOR]

Considerable effort has been devoted to the characterization of thermal properties of the different types of materials that can be used as thermal energy storage (TES) media, but scarce literature exists concerning the materials to manufacture the tanks that can be used to contain these storage media. One of the main concerns when selecting the most suitable material for these tanks is its resistance to corrosion due to molten salts that constitute the TES system. Dynamic gravimetric analysis is a newly proposed method for the study of corrosion on metals, which optimizes the standard procedure described by ASTM G1–03. The new technique avoids the direct handling of samples, so more accurate values can be obtained. In this work, the resistance to corrosion of AISI 316 stainless steel samples in contact with commercial grade molten salts of the Li 2 CO 3 -Na 2 CO 3 -K 2 CO 3 system, at 600 °C for different exposure times, has been determined by using this new methodology. The results show that the initial corrosion rate is lower at higher amounts of lithium carbonate present in the molten salts mixture. [ABSTRACT FROM AUTHOR]

In this review article, waste materials (biogenic/non-biogenic) are focused as the flocculants for harvesting of algal biomass. Chemical flocculants are widely utilized for the effective harvesting of algal biomass at a commercial scale while the high cost is a major drawback. The waste materials-based flocculants (WMBF) are started to utilize as one of the cost-effective performance for dual benefits of waste minimization and reuse for sustainable recovery of biomass. The novelty of the article is articulated with the objective that presents an insight of WMBF, classification of WMBF, preparation methods of WMBF, mechanisms of flocculation, factors affecting flocculation-mechanism, challenges and future recommendations that are required for harvesting of algae. The WMBF are shown similar flocculation mechanisms and flocculation efficiencies as chemical flocculants. Thus, the utilization of waste material for the flocculation process of algal cells minimizes the waste load into the environment and transforms the waste materials into valuable resources. [Display omitted] • Potential of waste materials as flocculants (WMBF) assessed for biomass harvesting. • Biogenic materials has high flocculation efficiency compared to non-biogenic materials. • Classification of WMBF and mechanism of flocculation has elucidated. • WMBF has similar flocculation mechanisms and efficiency as chemical flocculants. • Promising alternatives, challenges and future prospects of WMBF are discussed. [ABSTRACT FROM AUTHOR]