• Journal of Digital Convergence
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• v.15 no.9
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• pp.189-200
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• 2017

The purpose of this study is to identify the characteristics of China's trade relationships with and dependency on the countries participating in the Belt and Road initiative and to present some implications. This study collected annual total imports, exports, and GDP data from the International Monetary Fund (IMF) on 198 countries and the National Bureau of Statistics of China (NBS) on 221 countries from 1995 to 2015. China's imports and exports have expanded considerably from the mid-1990s to the present, and China's dependence on imports and exports with the US and Japan has declined, while its dependence on the Middle East, South Africa, South America, and Southeast Asia has increased. China has a very high level of dependence on imports from and exports to the countries participating in the Belt and Road initiative, and as the Belt and Road project progresses, the mutual trade dependency between China and the other participating countries is expected to strengthen and expand.

• Resources Recycling
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• v.30 no.3
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• pp.18-29
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• 2021

Platinum group metals (PGMs) are used in a wide range of application fields such as catalysts, electronic devices, electrodes, electrical devices, fuel cells and high temperature materials due to their excellent electrical and thermal conductivity as well as chemical resistivity. Platinum group elements are generally associated with nickel-copper sulfides in magmatic rocks. Depending on the relative concentrations of the PGMs, they are produced either as the primary products or as by-products of the nickel and copper. However, PGMs natural resource deposits are strictly limited in countries such as South Africa and Russia. The annual supply of PGMs is only under 500 t. Considering the limited supply of PGMs, there will be a noticeable increase in the supply risk associated with PGMs in the near future. Therefore, it is extremely important to recover PGMs from secondary resources such as spent catalysts. This paper reviews on overview of PGMs extraction and recycling processes.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.4
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• pp.445-449
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• 2005

Present study was designed to evaluate the practical application of triethyl amine(TEA) injection for improving the collection efficiency of electrostatic precipitator(ESP) connected to a real operating plant. The major fuels used at the domestic power stations were bituminous coals imported from Australia, China, South Africa, and USA. Although the values of the electric resistance would be more or less different according to the type of the coals used, the unique electric resistance values of fly ash from the coals were mostly higher than $1{\times}10^{12}\;{\Omega}-cm$ and therefore, back corona problems were always expected to occur in the electrostatic precipitator. The particulates concentrations, smoke concentrations and their electric resistivity measured at the outlet of ESP, and the inspection of collection indicated that the injection of TEA improved the collection efficiency of particulate at collection plates of ESP. The electric resistance for, fly ash with the injection concentration of TEA 15 ppm(Purity 99.7%) was lowered to $2.1{\times}10^{11}\;{\Omega}-cm$ after injection from $1.9{\times}10^{12}\;{\Omega}-cm$ before injection. Under this condition, the dust emission content at the stack was reduced to approximately 80%, lowering the average outlet concentrations of particulates from $70\;mg/Sm^3$ to $14\;mg/Sm^3$.

• Journal of Environmental Policy
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• v.11 no.3
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• pp.149-170
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• 2012

The United Nations Climate Change Conference, Durban 2011, ended on December 12, 2011, 36 hours over its schedule, delivering the Durban Package, which consisted of, inter alia, the extension of the period for Kyoto Protocol term and the launch of Ad-hoc working Group on the Durban Platform for Enhanced Action. Despite the positive progress made in Durban, the future of post-2012 climate regime still seems cloudy. Before the Durban conference, some of Annex I countries with emissions reduction commitment under the Kyoto Protocol's first commitment period openly declared their intention not to participate in the second one, reducing the effectiveness of Durban agreement. Parties to the conference have a long list of difficult issues disturbing the materialization of the new legal agreement in 2020 such as level of mitigation targets of individual countries and legal nature of their commitment. Given this uncertainty, the Korean government should reinforce its domestic climate policies rather than settling in the fact that it remains as a non-Annex I county party under the Durban Agreement due to the extension of the Kyoto Protocol period. Domestically, it needs to continue to raise the public awareness for rigorous climate policies to transit its economy to low carbon pathway which reduces the country's dependency on fossil fuel in the long term. It is also important to implement cost effective climate policies to cope with domestic resistance and international competitiveness. Internationally, its priority would be working for trust-building in the on-going negotiation meetings to encourage meaningful participation of all parties.

• Journal of Life Science
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• v.14 no.2
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• pp.291-295
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• 2004

Rooibos (Aspalathus linearis) (RB) is a leguminous shrub native to the mountainous areas of the northwestern Cape Province in South Africa. RB tea infusions are the fermentation products of its leaves and fine sterns, and known to have a high antioxidative activity due to the presence of flavonoids and phenolic acids. We investigated the effects of RB tea on the alleviation of oxidative stress on cultured rat cortical neurons in a hypoxic model. Measurement of lactate dehydrogenase (LDH) released into culture media revealed that RB increased cell viabilities in both normoxia (6-18%) and hypoxia (2-24%) dose-dependently (10-100 $\mu\textrm{g}$/ml) on 16 days in vitro (3 days after treatment). Visualization of cell morphology by expression of GFP-Hsc70 fusion protein showed that RB (50 $\mu\textrm{g}$/ml) reduced the average vacuolated soma from 55.4$\pm$4.59% (no RB addition) to 40.9$\pm$6.3% (RB addition) on 5 days after hypoxia. Our results proves efficacy of RB in the neuroprotection of hypoxic neurons and extend application for RB into the prevention and/or treatment of neuronal damages.

• Resources Recycling
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• v.26 no.3
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• pp.79-91
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• 2017

The core of Hydrogen Fuel Cell Vehicles (FCV) is polymer solid fuel cell (PEFC), and the core material that generates electrochemical electricity in the cell is platinum catalyst. Platinum is localized in South Africa and Russia, and the world production of Pt is about 178 tons per year, which is expensive and recycled. At present, the amount of Pt used in PEFC is $0.2{\sim}0.1mg/cm^2$. In order to reduce the price of the battery and increase the FCV supply, the target is to reduce the amount of Pt used to $0.05{\sim}0.03mg/cm^2$. $Pt-Pd/Al_2O_3$, Pt/C, Pt/GCB, Pt/Au/C, PtCo/C, PtPd/C, etc. by using polyol method using nano Pt, improved Cu-UPD/Pt substitution method and nano-capsule method, Have been researched and developed, and there have been reported techniques for improving the activity of Pt catalysts and stabilizing them. This paper investigates the production technology of nano-Pt and nano-Pt catalysts, recycling of spent Pt catalysts and application trends of Pt catalysts.

• Journal of Practical Agriculture & Fisheries Research
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• v.8 no.1
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• pp.30-42
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• 2006

This experiment was conducted to investigate current situation and plant grouping by light and watering of mingled several cacti and succulents in a pot. The main 11 cacti are consist of Myrtillocactus geometrizans (Mart.) Cons., Gymnocalycium mihanovichii var. friedrichii Werd., Marginatocereus marginatus(DC.) Backbg., Eriocactus leninghausii (Hge. Jr.) Backbg, Notocactus scopa (Spreng.) Berg., Lobivia nealeana Backbg., Mammillaria elongata var. intertexta (DC.) SD., Pseudoespostoa (Vp1.) Backbg., Mammillaria albilanata Backbg., Mammillaria klissingiana Bod. and Espostoa lanata (HBK.) Br. & R. The main 10 succulents are Kalanchoe thyrsifolia Harv., Portulacaria afra var. foliis-variegatis Jacobs., Crassula perforata Thunbg., Echeveria pulvinata Rose, Aeonium arboreum cv. atropurpureum., Echeveria lauii Moran & J. Meyran, Pachypodium lamerei Drake, Sedum rubrotinctum cv. Aurora Boom., Aloe mitriformis Mill., and Euphorbia coerulescens Haw. The cacti were native to Mexico, Brazil, Peru, Paraguay, Ecuador, etc. The sucullents were native to Mexico, Africa, Gran Canaria, Madagascar, etc. Most of all the cacti and sucullents in the experiment are growing well under full sun or light shade, however Portulacaria afra var. foliis-variegatis Jacobs, and Sedum rubrotinctum cv. Aurora Boom. did not influenced by light. And all the plants require a little or moderate watering. Thus, planting by similar required water and light, when growing in a pot of several cacti and succulents, might be decreased the rate of death causing by their different plant physiology.

• The Journal of the Petrological Society of Korea
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• v.4 no.2
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• pp.104-123
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• 1995

Mantle xenoliths in alkali basalt from Boun, Gansung area, and Baegryung island in S. Korea are spinel lherzolites composed of olivine, orthopyroxene, clinopyroxene, and spinel. The xenoliths generally show triple junctions among grams, kink-banding in olivine and pyroxenes, and protogranular and eqigranular textures having m orlentatron of specific direction. Anhedral brown spinels are disseminated in the intergranular spaces of minerals. Mineral compositions are very homogeneous without compositional zonation from rim to core in grains regardless different locahties. Olivine shows Fo. component of 89.0-90.2 and low CaO of 0.03-0.12wt%, orthopyroxene is enstatite with En component of 89.0 - 90.0 and $Al_2O_3$ of 4-5wt%, and clinopyroxene is diopside having En. component of 47.2-49.1 and $Al_2O_3$ of 7.42-7.64wt% from Boun and 4.70-4.91wt% from Baegryung showing local variation. Spinel shows the distinctive negative trend with increasing of A1 and decreasing of Cr, and Mg value and Cr number are 75.1-81.9 and 8.5-12.6, respectively. To estlmate T and P for these mantle xenoliths pyroxene-geothermometers (Wood and Banno, 1973; Wells, 1977; Mercier, 1980; Sachtleben and Seck, 1981; Bertrand and Mercier, 1985; Brey and Kohler, 1990) and Al-solubility geobarometer (Mercier, 1980; Lane and Ganguly, 1980) are used. Temperatures of Mercier (1980) and Sachtleben and Seck (1981) are compatible and equilibrium temperatures of xenoliths, average value of these two, aiie from $970^{\circ}C$ to $1020^{\circ}C$, and equihbrium pressures derived from Mercier (1980) are in the range of 12-19 Kb (42-63 Km). These temperatures and pressures seem to be reasonble wlth the consideration of Al-isopleths in MAS system (Lane and Ganguly, 1980) and Fe effect on Al-solubility in orthopyroxene (Lee and Ganguly, 1988). Equllibrium of temperatures and pressures of xenoliths in P-T space belong to ocenanic geothem among the Mercier's mantle geotherms (1980) and are completely different from continental geotherms of S. Africa (Lesotho) and S. India having different geologcal ages. anera1 compositions of spmel-lherzohtes in S. Korea and eastern China are primitwe and paleogeothems of both are very s~mllar, but degrees of depletion of upper mantle could be locally different from each other since eastern China has various depleted xenoliths due to different degrees of partial melting.

• Food Science and Preservation
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• v.15 no.4
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• pp.582-586
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• 2008

Total phenolic compounds and antioxidative activities of rooibos tea(Aspalathus linearis) fractions were studied. Three extracts, using hexane, ethyl acetate, and ethanol, were prepared. Total phenolic compounds were 3069.3 mg/100 g extract in the hexane fraction, 18604.4 mg/100 g extract in the ethyl acetate fraction, and 13458.8 mg/100 g extract in the ethanol fraction. Levels of vanillic acid, caffeic acid, syringic acid, 4-coumaric acid, and ferulic acid were analyzed by RP-HPLC, and totals of 3452.6 and 3156.1 mg/100 g of extract were found in the ethanol and ethyl acetate fraction, respectively. In the DPPH assay, the ethanol fraction(82.2% of contol) and the ethyl acetate fraction(78.9%) showed the highest free radical scavenging capacities. The induction period of each tea fraction in the fish oil rancimat assay was measured. When 500 ppm of the ethanol fraction was applied, a 1.19 h induction period was observed. This was 2-fold greater than the induction period of the control.

• Journal of the Korean Association of African Studies
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• v.29
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• pp.27-53
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• 2009

At the start of the new century, South Africa probably had the largest number of HIV-infected people of any country in the world. The only nation that comes close is India with a population of one billion people compared to South Africa's figure of 57 million. The tragedy is that this did not have to happen. South Africa was aware of the dangers posed by AIDS as early as 1985. In 1991, the national survey of women attending antenatal clinics found that only 0.8percent were infected. In 1994, when the new government took power, the figure was still comparatively low at 7.6 %. The 2004 figure which has been published is 26.5%. This article tracks the epidemic globally, in the region and in South Africa. I explain some of the basic concepts around the disease and look at what may happen with respect to numbers. The situation is bad, and the number of people falling ill, dying and leaving families will rise over next few years. This will impact on South Africa in a number of important ways. This article assesses the demographic, economic and social consequences of the epidemic. It disposes of a number of myths and present the real facts. The AIDS in South Africa is not related to individuals only. It warns that AIDS in Africa is becoming a community and systemic problem. The acuteness of the problem does not stem merely from the fact that communities are affected, or could even be wipe out by the end of this decade, but from the fact that AIDS will place incredible burdens and obligations upon medical services, health care and religious communities such as churches. The facts confront churches' mission with the important question: who is going to take care of all the patients and where? The reality is that people dying of AIDS will have to be cared for at home by relatives and friends. A further question that arises is whether our people are prepared for this. AIDS was considered to be a homo-plague and the hunt was on for a scapegoat in the light of the fatal implication of the disease. At present we are in the strategic phase where we all realize that it will be of no avail to scare people with the ominous threat of AIDS AIDS destroys the optimism of our achievement ethics. This exposure of the culture of optimism is also an exposure of the so-called 'human basic fear which accuses Christianity that their concept of sin is a damper on man's search for liberation and basic need to be freed from all Imitation. AIDS is also a test for our ecclesiastical genuineness and the sincerity of our mission sensibility. It poses the question: How unconditional is Christian love? Is there room for the AIDS sufferer in the community of believers, despite the fact he is an acknowledged homosexual? The question to put to the church is whether the community of believers is an exclusive to put to the koinonia which excludes homosexuals. They may be welcome on principle, but in actual fact are not acceptable to the church community. As South Africa enters the new century, it is clear that the epidemic is not having a measurable impact. However, the impact of AIDS is gradual, subtle and incremental. The author's proposal of what is currently most needed in South Africa is that the little things will make a difference. It's about doing lots of little things better at grassroots level, with the emphasis on doing. There are so many community, churches and NGOs initiatives worth building on and intensifying. One must not underestimate the therapeutic value of working together in small groups to overcome a problem