Climate change has severely impacted food security and agricultural productivity in Africa. The scarcity of rains and the severe drought affecting the Sub-Saharan and the horn of Africa have impoverished the soil, and water resources, and have caused the death of livestock in countries like Sudan, Ethiopia, Kenya, Niger, and etc. On the other hand, the usage of chemical fertilizers for soil and crop nutrients is becoming an economic and environmental burden for African farmers. Thus, the necessity to implement sustainable agricultural technics to maintain and improve soil fertility by applying natural nutrients obtained from livestock manure while livestock is fed with crop residues in a single agricultural area. Although this farming system offers environmental and economic benefits to farmers, particularly in the rural and semi-urban areas, its implementation is very low in Africa because of: 1) constant migration of herders in the search of green pasture for livestock, making the collection of manure difficult, 2) religious and traditional beliefs considering animal waste as not being pure to be applied on crops, 3) conflicts between herders and farmers over the control of water resources and arable lands, making the cohabitation of livestock and crops in one farmland unlikely, and 4) the habit of crop residues burning, which is not just harmful to the environment but also a waste of natural livestock fed. Based on the reviewed literature, the Korea-Africa Food and Agriculture Cooperation Initiative (KAFACI) plans to develop and implement an integrated crop-livestock project in KAFACI member countries with the mission 1) to diffuse the importance of using natural nutrients for improving soil fertility and enhancing crop and livestock productivity in Africa, 2) to train researchers and farmers on new technologies for manure treatments, 3) to demonstrate the benefits of using livestock manure for soil fertility, crops nutrients, while using crop residues as livestock nutrients, and 4) contribute to enhancing sustainable agriculture in Africa through the reduction of greenhouse gas by reducing livestock’s waste and crop residues burning.

The Democratic Republic of Congo (DR Congo) is a central African country, abundant with large and various agro-ecological landscapes suitable for the cultivation of various crops, water resources, and a young manpower. However, the country is facing a severe food crisis, exposing around 27 million people, among which 4 million undernourished children to famine according to the World Food Program. To better understand the paradox of the country with huge agricultural potential being one of the countries with the largest number of people in food distress in 2022, we reviewed the DR Congo's current agricultural potentials and challenges, and it was observed that the country's low agricultural productivity is mainly due to low governmental human and technological investment in agricultural research, which is characterized by insufficient training of researchers, limited research budget, and lack of updated technologies. Also, the country's immensity and poor transport infrastructures make the movement and commercialization of crops difficult in the country. Based on the data reviewed, the Korea-Africa Food & Agriculture Cooperation Initiative, an organization in which the DR Congo is a member country, proposes a reform of the country's agricultural policies 1) to set a proper vision for the country's Agricultural research and productivity, 2) to design a proper structure assigning the roles of every organization involved in agriculture at the national or provincial level, 3) to improve the government investment in young researchers' capacity building and motivation, 4) to define how cooperation with international organizations could contribute to the enhancement of the country's agricultural development.

한-아프리카 농식품기술협력 협의체 KAFACI(Korea-Africa Food and Agriculture Cooperation Initiative)는 2010년 7월 아프리카 16개국과 한국을 포함하여 17개 회 원국으로 출범하였다. KAFACI는 농촌진흥청(농진청) 주도의 농업연구개발 다자간 협력 사업으로 아프리카의 공통 농업현안 해결을 목표로 한다. 그러나 출범 당시 농진청은 아프리카 농업연구개발에 대한 경험이 부족하였고, 아프리카 국가들도 한국 농업연구에 대해서 아는 바가 거의 없었다. 따라서 농진청-아프리카 농업연 구소 간 상호이해와 협력관계 구축이 시급하였으며, 이를 위하여 출범 후 5년 동 안은 각 회원국이 희망하는 분야의 농업기술을 개발하는 국별과제에 집중하였다. 이를 통하여 구축된 협력관계를 바탕으로 2015년 3차 총회에서 국별과제를 다자 협력에 적합한 분야별 사업으로 개편하고, 기초·식량·원예·축산·농촌지도 5개 분야 협력과제를 착수하였다. 이러한 분야별 공통현안 발굴 및 추진 체계는 현재 까지 지속되고 있다. KAFACI는 분야별 협력체계 구축과 병행하여 성과의 조기 도 출을 위한 중점 분야 발굴을 시도하였다. 세네갈, DR콩고, 카메룬이 추진한 벼 관 련 국별과제와 아프리카녹색혁명동맹(AGRA)과의 협력으로 추진한 약배양기술 적 용 벼 품종 개발을 통하여 아프리카 벼 육종 사업의 필요성과 가능성을 확인하고 본격적인 벼 개발 협력사업을 기획하여 예산을 확보하였다. 2016년 아프리카벼연 구소(AfricaRice)와 공동으로 9년간의 ‘아프리카 벼 개발 파트너십‘ 과제를 착수 하였다. 2017년에 세네갈 생루이 소재 AfricaRice 사헬센터에 약배양연구실을 설 치하고 벼 육종전문가를 파견하였다. KAFACI는 한국의 통일형 벼와 각 회원국의 유전자원을 활용하고, 약배양기술을 적용하여 우수계통을 선발하고 있으며, 현재 까지 회원국에 총 1,547 계통을 제공하였다. 이와 병행하여 회당 4~5명의 연구원 을 사헬센터로 초청하여 벼 재배 전기간에 걸친 벼 육종훈련을 연 2회, 총 5회 추 진하여 회원국 벼 육종역량 강화에 기여하였다. 회원국에서는 제공받은 우수계통 에 대한 지역적응시험 및 농민참여선발을 추진하여, 현재까지 5국에서 11품종을 등록하였다. 이러한 성과와 추진방식은 유튜브 동영상 ’한국 통일벼와 사랑에 빠 진 아프리카‘을 통하여 국내에서 주목을 받았으며(2022.8.10 기준 132만회 조회), 2021년 OECD 공공부분 혁신 우수사례(OPSI, Observatory of Public Sector Innovation)로 채택되었다. KAFACI 벼 사업이 조기에 품종등록 성과를 도출할 수 있었던 주 요인 중 하나는 단순 양자 또는 다자협력을 틀을 넘어 농진청-국제연 구기관-회원국의 삼각협력으로 추진되었다는 점이다. 한국이 보유하고 있는 기술 을 현장이해도가 낮은 상황에서 개발도상국에 직접 전달하기보다는 국제기관의 경험 및 인프라와 결합하여 전수하는 삼각협력 방식은 다른 분야 국제개발협력 사업에도 적용가능한 모델이다.

A composite photocatalyst of zinc oxide (ZnO) nanoparticles decorated with different content of reduced graphene oxide (rGO) was prepared via a simple and facile one-step method in this paper. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectra, and UV–Vis diffuse reflection spectroscopy (UV–Vis DRS) were used to characterize the crystal structure, morphology and optical properties of the rGO–ZnO composite photocatalyst. The photocatalytic properties of the composites were investigated using methyl orange (MO), a typical orange compound, as a test pollutant. The results showed that rGO–ZnO composites displayed significantly enhanced photocatalytic activity in MO degradation than pure ZnO, and the pseudo-first-order kinetic constant on the optimal rGO–ZnO composite was 14 times as great as that on pure ZnO. The enhanced photocatalytic ability of the rGO-ZnO composites was mainly benefited from the high specific surface area and high conductivity of rGO, which facilitated efficient charge separation in the rGO-ZnO nanocomposite.

Nitrophenol sensors have garnered interest in pharmaceuticals, agriculture, environment safety and explosives. Various methods have been proposed to detect 4-nitrophenol, but nitrophenol isomers such as 2,4-dinitrophenol (DNP) and 2,4,6-trinitrophenol have been comparatively less studied. For the first time, the present work explores graphitic nanocarbon, i.e., carbon black (CB) interface for sensing of DNP. Two reduction potentials were noted at − 0.48 and − 0.64 V for o-NO2 and p-NO2 moieties, respectively, at CB/GCE. At the same time, bare GCE (glassy carbon electrode) shows a single reduction potential at − 0.7 V. The electrocatalytic effect and adsorption ability of the interface was studied from the DNP concentration effect. Scan rate and pH studies suggest that the CB acquires four electrons for NO2 reduction by the diffusion phenomenon. A broad detection range of 10–250 μM DNP with a very low detection limit of 0.13 (o-form) and 0.15 μM (p-form) was achieved using the CB interface. The real-time applicability of the fabricated sensor was evaluated using commercially available beverages with excellent recovery values. The stability, repeatability and reproducibility of the CB interface were successfully confirmed. Comparison of the sensing parameters of the developed sensor with those reported in literature reveals excellent detection limit and response time for the CB-interfaced DNP sensor, indicating its potential for environmental and commercial applications.

Acrylonitrile–butadiene–styrene (ABS) terpolymer was compounded with short carbon fiber (CF) and carbon nanotube (CNT) using a micro-extruder followed by the injection molding process. Composite samples were fabricated with loading ratios of 20 wt.% CF and 0.1, 0.5 and 1.0 wt.% of CNT. Mechanical, electrical, thermo-mechanical, thermal, melt-flow, and structural investigations of ABS-based composites were conducted by performing tensile, impact, hardness, and wear tests, conductive atomic force microscopy (AFM), dynamic mechanical analysis (DMA), thermal gravimetric analysis (TGA), melt flow rate test (MFR), scanning electron microscopy (SEM) characterization techniques, respectively. According to mechanical test data of resultant composites including tensile and impact test findings, CNT additions led to the remarkable increase in tensile strength and impact resistance for CF reinforced ABS composites. The formation of synergy between CNT nanoparticles and CF was confirmed by electrical conduction results. The conductive path in ABS/CF composite system was achieved by the incorporation of CNT with different loading levels. SEM micrographs of composites proved that CNT nanoparticles exhibited homogeneous dispersion into ABS matrix for lower loadings.

This work provided a review of three techniques—(1) spectrochemical, (2) electrochemical, and (3) spectroelectrochemical– for molten salt medias. A spectroelectrochemical system was designed by utilizing this information. Here, we designed a spectroelectrochemical cell (SEC) and calibrated temperature controllers, and performed initial tests to explore the system’s capability limit. There were several issues and a redesign of the cell was accomplished. The modification of the design allowed us to assemble, align the system with the light sources, and successfully transferred the setup inside a controlled environment. A preliminary run was executed to obtain transmission and absorption background of NaCl-CaCl2 salt at 600°C. It shows that the quartz cuvette has high transmittance effects across all wavelengths and there were lower transmittance effects at the lower wavelength in the molten salt media. Despite a successful initial run, the quartz vessel was mated to the inner cavity of the SEC body. Moreover, there was shearing in the patch cord which resulted in damage to the fiber optic cable, deterioration of the SEC, corrosion in the connection of the cell body, and fiber optic damage. The next generation of the SEC should attach a high temperature fiber optic patch cords without introducing internal mechanical stress to the patch cord body. In addition, MACOR should be used as the cell body materials to prevent corrosion of the surface and avoid the mating issue and a use of an adapter from a manufacturer that combines the free beam to a fiber optic cable should be incorporated in the future design.

This experiment was conducted to investigate the change in the productivity of Italian ryegrass seeds according to the inter-row spacing in the southern region of the Korean Peninsula. Italian ryegrass (Lolium multiflorum Lam.) ‘Green Call’ variety was sown in Jinju, Gyeongnam in the fall of 2020 with three inter-row spacings (20, 30 and 40 cm). The experiment was arranged a randomized block design with three replications. The ryegrass was sown on October 17, 2020, and the harvest was on May 31, about 60 days from the first heading stage. There was no difference among treatments with an average of April 27th in heading stage. Plant height was significantly longer at 30 cm seeding interval and the shortest in 20 cm treatment. The length of the spike was the longest in the 40 cm seeding interval, and the number of seeds per spike was the highest in the 20cm seeding interval, but there was no significant difference among treatments. The seed yield was the highest at the 20 cm sowing interval (2,180 kg/ha), and decreased as the spacing increased. The dry matter content of seeds and straw was found to be 44.90% and 45.51% on average, and there was no significant difference among treatments. The amount of remaining straw after harvesting was found to be 7,506 kg/ha on average on DM basis, and was high at the 20 cm seeding interval. In view of the above results, it was found that it is most advantageous to sow at intervals of 20 cm when producing Italian ryegrass seeds through autumn sowing in the southern region.

Effect of sulfation processes on the physicochemical properties of ZrO2 and TiO2 nanoparticles were thoroughly investigated. SO4/ZrO2 and SO4/TiO2 catalysts were synthesized to identify the acidity character of each. The wet impregnation method of ZrO2 and TiO2 nanoparticles was employed using H2SO4 with various concentrations of 0.5, 0.75, and 1 M, followed by calcination at 400, 500, and 600 °C to obtain optimum conditions of the catalyst synthesis process. The highest total acidity was found when using 1 M SO4/ZrO2-500 and 1 M SO4/TiO2-500 catalysts, with total acidity values of 2.642 and 6.920 mmol/ g, respectively. Sulfation increases titania particles via agglomeration. In contrast, sulfation did not practically change the size of zirconia particles. The sulfation process causes color of both catalyst particles to brighten due to the presence of sulfate. There was a decrease in surface area and pore volume of catalysts after sulfation; the materials’ mesoporous structural properties were confirmed. The 1 M SO4/ZrO2 and 1 M SO4/TiO2 catalysts calcined at 500 °C are the best candidate heterogeneous acid catalysts synthesized in thus work.

Porous basalt aggregate is commonly used in roadbed engineering, but its application in concrete has rarely been studied. This paper studies the application of porous basalt in concrete. Porous basalt aggregate is assessed for its effects on mechanical strength and durability of prepared C50 concrete; because it has a hole structure, porous basalt aggregate is known for its porosity, and porous basalt aggregates can be made full of water through changing the content of saturated basalt; after full-water condition is achieved in porous basalt aggregate mixture of C50 concrete, we discuss its mechanical properties and durability. The effects of C50 concrete prepared with basalt aggregate on the compressive strength, water absorption, and electric flux of concrete specimens of different ages were studied through experiments, and the effects of different replacement rates of saturated porous basalt aggregate on the properties of concrete were also studied. The results show that porous basalt aggregate can be prepared as C50 concrete. For early saturated porous basalt aggregate concrete, its compressive strength decreases with the increase of the replacement rate of saturated aggregate; this occurs up to concrete curing at 28 d, when the replacement rate of saturated basalt aggregate is greater than or equal to 40 %. The compressive strength of concrete increases with the increase of the replacement rate of saturated aggregate. The 28 d electric flux decreases with the increase of the replacement rate of saturated aggregate, indicating that saturated porous basalt aggregate can improve the chloride ion permeability resistance of concrete in later stages.

To investigate the domestic seed production potential of Italian ryegrass, it was sown in autumn in the southern region and harvested in the spring of the following year to investigate the productivity and quality of seeds and straw. Italian ryegrass (Lolium multiflorum Lam.) ‘GreenCall’ variety was sown in Jinju, Gyeongnam in the fall of 2020 with three seeding rates (20, 30 and 40 kg/ha). The experiment was arranged consisted of a randomized block design with three replications. The ryegrass was sown on October 17, 2020, and the harvest was on May 31, about 60 days from the heading stage. The heading stage of Italian ryegrass was April 28, and there was no difference among treatments. Plant height was significantly shorter in the 40 kg/ha seeding treatment group, and there was no significant difference in the remaining treatments. The resistance of lodging, disease, and cold did not show significant differences among treatments. Spike length and number of seeds per spike were highest at 20 kg/ha seeding amount, and there was no difference in the remaining treatments. The seed yield was the highest at 1,956 kg/ha in the 20 kg/ha seeding rate, and there was no difference in the 30 and 40 kg/ha seeding rates. The dry matter content of seeds and straws was 45.60 and 41.83% on average, and there was no significant difference among treatments. The amount of remaining straw after seed harvesting was found to be 7,689 kg/ha on average on a dry basis, and it was high in the 40 kg/ha sowing area, but there was no significant difference among treatments. According to the above results, it was found that it is most advantageous to sow at 20 kg/ha when producing Italian ryegrass seeds through autumn sowing in the southern region.

최근 살진균제는 세계 식량 안보에 없어서는 안될 필수 요소이며, 그 사용량은 증가하고 있다. 살진균제는 직접적 또는 간접적으로 곤충에 영 향을 미쳐 유전자 및 분자 수준의 변화를 일으킨다. 곤충은 다양한 해독 매커니즘을 통해 살진균제를 포함한 농약으로부터 유발되는 활성산소 (ROS) 독성을 제거한다. 본 연구는 살진균제 캡탄의 비치명적 투여량(0.2, 2, and 20 μg/μL)을 주입 후 갈색거저리의 유충에서 해독효소의 mRNA 발현량을 분석했다. 갈색거저리의 전사체 분석을 통해 해독 매커니즘 관련 유전자인 퍼옥시다제(POX), 카탈라제(CAT), 슈퍼옥사이드 디스뮤타제(SOD) 및 글루타티온-S-트랜스퍼라제(GST)를 발굴하였다. 처리 24시간 후 TmPOX5 mRNA가 유의하게 증가한 것으로 나타났다. 처리 3 시간 후 TmSOD4의 mRNA가 유사하게 증가하였다. 또한 2 μg/μL 처리 24시간 후 TmCAT2의 mRNA 가 유의하게 증가하였다. 캡탄 노출 후 TmGST1 및 TmGST3의 mRNA 발현량도 증가하였다. 결론적으로, TmPOX5 및 TmSOD4 유전자는 갈색거저리에서 캡탄 노출에 대한 바이오마커 또는 생체이물 센서로 작용할 수 있음을 시사한다.

Green synthesis of graphene using leaf extracts as sustainable reducing and capping agents is a thrust area of research owing to its simplicity, eco-friendly nature and the ease of access to graphene. Moringa (Moringa oleifera Lam) plant is widely cultivated in India owing to its important medicinal and nutritional values. Inspired by these reports, herein we report a simple, green and economic synthesis of graphene, Moringa leaf extract employed reduced graphene oxide (MRGO) with excellent dye removal efficiencies. The MRGO is prepared by refluxing a mixture of aqueous dispersion of graphene oxide and Moringa leaf extract for 10 h. Further, we elucidated the role of synthesized MRGO in the removal of methylene blue (MB) and rhodamine B (RB) dyes through the sonochemical method. This as-synthesized material exhibited excellent dye removal efficiencies of about 93% and 87% against MB and RB dyes, respectively. Graphene with huge surface area expedited the better adsorption of dye molecules, thus, facilitated the better removal of the latter. Therefore, the superior dye removal efficiencies of MRGO were attributed to its adsorption capacity. This cost-effective synthetic approach of MRGO nanomaterial has a great potential for the innovative applications in water purification technology and find its place in further industrialization.

Double-layer graphene nanoribbons promise potential application in nanoelectromechanical systems and optoelectronic devices, and knowledge about mechanical stability is a crucial parameter to flourish the application of these materials at the next generation of nanodevices. In this paper, molecular mechanics is utilized to investigate nonlinear buckling behavior, critical buckling stress, and lateral deflection of double-layered graphene nanoribbons under various configurations of stacking mode and chirality. The implicit arc-length iterative method (modified Riks method) with Ramm’s algorithm is utilized to analyze the nonlinear structural stability problem. The covalent bonds are modeled using three-dimensional beam elements in which elastic moduli are calculated based on molecular structural mechanics technique, and the interlayer van der Waals (vdW) interactions are modeled with nonlinear truss elements. An analytical expression for Young’s modulus of nonlinear truss elements is derived based on the Lennard–Jones potential function and implemented in numerical simulation with a UMAT subroutine based on FORTRAN code to capture the nonlinearity of the vdW interactions during the buckling analysis. The results indicate that the highest critical buckling stress and the minimum lateral deflection occur for armchair and zigzag chirality, both with AB stacking mode, respectively. Moreover, the critical buckling stress is found to be directly dependent on the mode shape number regardless of in-phase or anti-phase deflection direction of layers. Lateral deflection exhibits a similar trend with mode shape in anti-phase mode; however, it is decreasing by increasing mode shape number in in-phase mode.

The optimal determination of seeding rate is critical to minimizing uncertainties about the large variations observed in forage quality and productivity when alfalfa is cultivated under different geographical areas and growing conditions. The objective of this investigation was to provide information about the proper seeding rate according to harvest timing for alfalfa cultivation in the Northern regions of Korea. Alfalfa was sown in September 2018 at a seeding rate of 20, 30 or 40 kg/ha and harvested four times in 2019: May 3, July 2, September 11, and October 13. Regardless of seeding rate, alfalfa plant height was longest at the third harvest (113 cm) and the shortest in the last annual harvest (43.8 cm). However, seeding rate had no effect on alfalfa plant height at any harvest. Forage relative feed value was increased in the first cutting but decreased in the third cuttings as seeding rate increased. However, seeding rate had slight effect on alfalfa forage quality components at the second and fourth cuttings. Total annual DM and crude protein production (in 4 harvests) was greater at higher seeding rates. Plots seeded at a rate of 40 kg/ha produced on average 1,257 and 2,620 kg/ha more forage (DM basis) than those seeded at a rate of 30 or 20 kg/ha, respectively. Forage DM production at the first, second, third, and fourth harvests accounted for 36.1, 24.0, 27.1, and 12.8 % of total annual DM production, respectively. Overall, small differences were seen when alfalfa seeding rate was different but maximum forage DM production (in four harvests) was detected when seeding rate was 40 kg/ha. These data could be useful to the alfalfa growers by allowing them to make more accurate trade-offs between seed price and the expected magnitude of forage yield gains in order to select the best seeding rate.