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      • 소 난포란의 체외수정에 있어서 정액의 처리방법이 수정 및 체외발달에 미치는 영향

        정현승,정장용,박희성 진주산업대학교 농업기술연구소 1996 農業技術硏究所報 Vol.9 No.-

        본 연구에서는 도살장에서 도살되는 한우의 난소를 적출하여 난소로부터 미성숙 난포란을 회수하여 체외에서 성숙한 난자를 동결정액과 정소상체미부 정액을 처리 방법에 따른 수정 및 체외발달에 미치는 영향을 조사하고자 본 실험을 수행하였다. 도살장에서 도살된 한우의 난소를 채취하여 체외성숙을 시킨 다음 한우 동결정액을 융해하여 B. O.배양액으로 원심분리를 2∼3회 반복하여 동해방지제를 제거한후 CO_2 incubator에서 0∼2시간 동안 swim-up을 유도하였다. 정소상체미부정자는 도축장에서 도살 직후 정소를 채취하여 체외수정에 사용하였다. 체외수정은 수정용 B. O.배양액 80∼100ul 당 10∼15개의 난자를 옮겨 정자의 최종농도가 2×10 exp (6) sperms/ml이 되게 첨가하여 약 24시간동안 CO_2 incu bator에서 수정을 유도하였다. 체외수정이 이루어진 수정란을 회수하여 10% FCS가 첨가된 TCM-199 배양액으로 4-5회 세척하여 monolayer를 형성하고 있는 난관상피세포와 공배양을 시키면서 48시간 간격으로 신선한 배양액으로 교환하면서 수정란의 체외발달을 유도한 결과는 다음과 같다. 체외수정율은 정소상체미부 정자를 사용하였을 때가 66.1%로서 동결정액을 사용하였을 때의 51.3% 보다는 유의적(P<0.05)으로 높았으며, 배반포로의 발달율은 각각 19.6 및 14.3%으로서 이들간에 유의적(P<0.05)인 차이가 없었다. swim-up처리 시간에 따른 수정율은 59.3∼63.4%의 수정이 이루어져 swim-up처리 시간에 따른 수정율은 유의적(P<0.05)인 차이가 없었으며, 체외수정란의 배반포로의 발달율도 13.6∼19.3%가 배반포로 발달하였으나 이들간에 유의적(P<0.05)인 차이는 없었다. The ovaries of Korean native cow or heifers were obtained from a slaughter house and kept on 28∼30℃ and transported to laboratory within 2 hrs. The follicular oocytes were collected follicles. The oocytes were matured in vitro for 24 hrs. in TCM-99 supplemented with 35ug/ml FSH, 10ug/ml LG, 1ug/ml estradiol-17 and granulosa cells at 39℃ under 5% CO_2 in air. The caudal epididymis of Korean native bulls were obtained from a slaughter house and transported to laboratory within 30 minutes. Swim-up of collected spermatozoa and Freezing sperm was layered under 2ml fertilization B. O. medium in two tissue culture tubes and held at a 45℃ angle for 0∼2 hour. They were fertilized in vitro by freezing sperm treated with heparin for 24 hrs., and then the zygotes were co-cultured in vitro with bovine oviductal epithelial cells for 7 to 9 days. The cleavage rate of matured oocytes was significantly(P<0.05) higher after in vitro fertilization in caudal epididyms(66.1%) than freezing sperm(513%). Similarly, the proporation of cleaved zygotes that developed to blastocysts was 19.6% and 14.3% respectively. The cleavage rate and in vitro developmental rate in swin-up period of freezing sperm was similar(59.3∼63.4% and 13.6∼19.3%).

      • KCI등재

        부신 우연종 132예에 대한 임상적 고찰

        정현승,김희정,김해성,김상완,신찬수,박도준,박경수,장학철,김성연,조보연,이홍규 대한내분비학회 2007 Endocrinology and metabolism Vol.22 No.4

        Background: Recently, the detection rate for adrenal incidentaloma in Korea has been on the increase. We describe here the clinical characteristics of these tumors and describe appropriate guidelines of diagnosis and treatment.Methods: We analyzed age, sex, location, size, function, and the pathological findings for 132 patients with an adrenal mass by CT, USG, and MRI undertaken for health examinations or non-adrenal disease from January 2000 to March 2005. Results: Adrenal masses were most commonly found in patients in their sixties (31%). 62.1% of the patients were men and 37.9% were women. For the location of the masses, 53% were found in the left gland, 43.2% were found in the right gland and 3.8% were found in both glands. Of all of the masses analyzed, 66% were 1 cm to 4 cm in size, and an adenoma-like appearance was the most common finding (69.7%) seen in images. All of the pheochromocytomas and carcinomas were above 4 cm in size. Patients with a functional mass were seen in 18 cases (13.6%) and pheochromocytomas were seen in 12 cases (67%). Three patients were found with cancer (2.3%), two cases (1.5%) of a primary carcinoma and one case of a metastasis (0.8%). Conclusion: The frequency and characteristics of benign nonfunctional, functional and malignant masses that were found in our hospital were similar to those presented in studies conducted outside of Korea. Therefore, it may be possible to apply previously established guidelines to domestic patients. 연구배경: 최근 들어 외국뿐 아니라 국내에서도 부신 우연종의 발견빈도가 증가하고 있다. 그러나 이 종괴의 특성에 대해 많은 외국 보고가 있어 왔으나 국내에서는 몇몇 보고를 제외하고 아직 연구가 충분하지 못한 실정이다. 따라서 국내에서 발견되는 부신 우연종에 대한 특성을 살펴봄으로써 외국에서 보고된 진료나 치료 지침이 우리나라 사람들에게도 적용될 수 있는지 알아보고자 본 연구가 의도되었다. 방법: 대상자는 2000년 1월부터 2005년 3월까지 건강 검진 및 부신 질환과 무관한 증세로 촬영된 CT, USG 및 MRI 등의 검사에서 부신 종괴가 발견된 총 132예를 대상으로 하여 연령대, 성별, 환자의 기왕력, 종괴의 위치 및 크기, 기능성 여부 및 조직학적 소견 등에 대한 빈도를 분석하였다.결과: 부신 우연종을 갖는 132명 중 60대에서 전체 종양의 31%가 발견되어 가장 높은 비율을 차지하였다. 성별로는 남성에서 62.1%, 여성에서는 37.9%가 발견되었다. 좌측 53%로 우측 43.2%보다 약간 높은 빈도였으며 양측성은 3.8%를 나타내었다. 크기에 있어서 1 cm 이상 4 cm 미만 크기의 종양이 전체의 66%를 차지하였고 이중, 69.7%가 영상촬영 소견에서 선종의 양상을 나타내었다. 갈색세포종과 악성 종양은 모두 4 cm 이상의 크기를 나타내었다. 기능성 종양은 132명 중 18명에서 나타났으며 이중 갈색세포종이 12명으로 67%를 차지하여 가장 높은 빈도를 나타냈다. 악성 종양은 132명 중 3명에서 나타났으며 2명은 원발성(1.5%), 1명은 전이성 종양(0.8%)이었다.

      • KCI우수등재

        지리산 면양목장조성에 관한 연구 제6보 지리산의 목초재배시험

        정현승,문점동,이종렬,김상철 ( H . S . Chung,J . D . Moon,J . R . Lee,S . C . Kim ) 한국축산학회 1974 한국축산학회지 Vol.16 No.1

        Orchardgrass, tall fescue, ladino clover, and alfalfa were sown on the plowed native grasslands of 600 to 900m altitude in the Mt. Chiri on September 10, 1970. Germinating date, winter survival ratio, plant length at each time of 5 successive cuttings, and the pasture yield through October, 1971 were observed. The soil properties of the fields were characterized as pH: 5.5 and loamy, and O.M. : 13.3%. The fertilizers such as N, P₂O_5, K₂O, lime, and borax were applied on the fields. And yield of native grasses, which were fertilized or not, was determined. 1. The germinating dates were ranged from September 19 to September 26 and were 2 to 3 days later on the upper lands. Tall fescue was germinated 2 to 4 days earlier than other pasture species and alfalfa was the latest germinating pasture species of them. 2. Orchardgrass showed the highest winter survival ratio (58.6 to 72.2%) and alfalfa showed the lowest (31.6 to 64.5%). The winter survival ratio of alfalfa and tall fescue decreased critically in the fields of 700 to 900 and 900m altitude, respectively. 3. The average plant length of 5 cuttings was ranged from 31.6 to 37.3 ㎝ in the 3 field locations. The shorter pasture grew in the higher altitude. The orchardgrass was longest in all the fields (45.0 to 58.2 ㎝). 4. Orchardgrass showed the most highest hay yield (719 to 825 ㎏/10a) and alfalfa showed the least (645 to 725 ㎏/10a). The native grasses showed the hay yield of 803 to 825㎏/10a in the non-fertilized plot and 877 to 829㎏/10a in the fertilized plot in the first year.

      • 智異山 大單位 緬羊牧場 開發의 必要性

        鄭鉉丞 진주산업대학교 1976 論文集 Vol.14 No.-

        The impotance of and major problems on the development of some large sheep farms on the Mt. Chir were discussed on the bases of the author's experiences on this subject. through 9 years. 1. Sheep production in the high mountaineous area has a great importance in the view of economical food and wool production with the increased land productivity and utillization of natural resources. 2. The major problems on the developing sheep farms on the Mt. Chiri were considered as follows: 1) Livestock industries are successful only by the longterm developing schedu1e. 2) Sheep production in Korea in general, is one of the underdeveloped livestock industries. 3) Any agricultural industry on the high mountaineous area has much disadvantage in traffical and social conditions. 3. The natura1 conditions were considered good for sheep farming and it was recommended for the succseeful development of sheep farms on the Mt. Chiri that the Government grant a long-term loan of 1ower interest and improve the traffical conditions, the scientists be trained more widely and intensively on sheep farming and the large enterprises have more interests in the development of national land resources.

      • 지리산 면양목장 조성에 관한 연구 : Ⅰ보. 면양목장 조성 및 면양사육 단지화 조성을 위한 기초조사 Ⅰ. Fundamental Survey of Resources for the Development of Sheep Range and Sheep Farm Grouping

        정현승,강봉태 진주산업대학교 1970 論文集 Vol.4 No.-

        This survey reports the availability of the various resources such as geography, meteology, traffic condition, soil property, labor resource, pasture distribution and water resource, for the development of sheep range and sheep-farm group, on the first step to the three-year plan in an area around the Forestry Experiment Station of Chinju Agricultural and Forestry Junior Teachnical College in Mt. Chiri. 1. The geographical conditions of the region found to be fit for the establishment of sheep range were as follows; longitude:127˚44'east,latitude:35˚22'north,elevation:600-900m above marine surface level, slope:5-25˚, total area: 280 ha, and administrative district: from high level flats to Yeo-gok and Dusuk village, Yupyung-ri, Samjang-myun, Sanchungkun, Kyung Sang Nam Do, Korea. Especially, eighty seven farm households and Karangip primary school distriduted around this region were found to be the reasonable resources for the development of sheep farm group in this region. 2. The soil of the area was composed of most of sand-loam with PH 5.3∼5.8, 2-5% of grit and 13.3% of humus (4.6-19.3%) among 30∼50㎝ depth of surface soil. These fertile soil properties were found to be fit for the development of pasture. 3. The meteological records of this region were found as follows: frosty period: from October 16 to April 22, yearly mean air temperature: 9.2℃ , ranging from 26.6℃ in August to (-)12 in January, annual rainfall: 2,346mm, yearly mean wind velocity: 6.2m/sec, direction of the wind: north-west in winter and south-east in summer. According to the above results from only one-year observation, the meteological conditions of this region were similar to those of Dae-Kwan Ryung area and were estimated to be favorable for sheep raising. 4. In this region 35 species of wild grasses were prosperous. The green yield of the grasses averaged 1,584㎏ per 10a and 0.87a was required for grazing a sheep. Therefore, it was estimated that about 3,000 heads of sheep would be well raised in this region. The fact that about 30 percent of Mt. Chiri area is available for sheep pasture suggested that 400,000㎏ of wool, or 250,000,000 won in price(equivalent to 1/10 of the total wool imported in 1967)could be gained from grazing about 100,000 heads of sheep in the whole area of Mt. Chiri, 54,000 ha. 5. Sufficient water resources, conclusive of mooring by the farmers around this region, irrigation water, underground water and especially the pond situated in high level flats were found to be available and the quality of water was satisfactory for watering sheep. 6. Concerning the traffic situation of this region, the construction of 1.5㎞ of road to Dusuk village (with 200m of bridge) and three 2㎞ range path from Dusuk village were required. However, such traffic problems are not serious because the sheep farming requires the road only for disposal of wool produced once a year. 7. From the managment survey for 87 farms around this area, it was found that each farm had 1,019.6 hours of unemployed labour per year, which was sufficient for raising 60 heads of sheep. So it could be estimated. that potential labour enough for raising 5,200 heads of sheep was reserved in this area. Moreover, the Karangip primary school boys are available as a good resource of labour for sheep grazing. The great deal of by-products of sericulture and potato-farming, which were the major industries in this region, was available for sheep raising.

      • 煉炭灰魚汁 吸着飼料의 添加가 돼지의 血液像에 미치는 영향

        鄭鉉丞,李乙熙,吳錫斗,宋瑛敏 진주산업대학교 농업기술연구소 1989 農業技術硏究所報 Vol.2 No.-

        煉炭灰魚汁 吸着飼料 添加가 돼지의 血液像에 미치는 영향을 조사하였다. 赤血球, 血色素量, 赤血球容積 및 血液球數는 무처리구에서 높은 편이고, 平均赤血球容積, 平均赤血球血色素量, 平均赤血球血色素濃度는 煉炭灰魚汁 吸着飼料 添加區에서 약간 높았으나, 白血球鑑別計數를 포함한 이들 모든 血液像은 정상치 범위내였다. The objective of this experiment is to investigate the effects of fish-soluble-absorbed-briquette-ash-added feed upon the hematological value of swine. RBC, hemoglobin, hematocrit and WBC were higher in the non-treated group. Mean corpuscular volume, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration were a little higher in the treated group. And all the above hematological values including differential count were within the normal range.

      • 통일벼 收穫後 再生 靑刈 볏짚의 租飼料 利用에 關한 硏究 : 第Ⅰ報 : 靑刈 收量 및 成分 調査 Ⅰ. On the green yield and chemical composition of the straw

        鄭鉉丞,尹東根 진주산업대학교 1975 論文集 Vol.13 No.-

        本 調査는 통일벼 收穫後 再生 靑刈 볏짚의 粗飼料로서의 利用性을 究明하고저 9월 27일 벼收穫後, 10월 18일과 28일, 2回 刈取한 再生 靑刈 볏짚 收穫量과 成分含量을 調査한 바 다음과 같은 結果를 얻었다. 1. 10a當 통일벼 收穫後 再生 靑刈 볏짚의 生産量은 150kg 程度였다. 2. 통일벼 收穫後 再生 볏짚의 成分 含量은 1975年 10월 18일 刈取한 것이 Crude protein 1.56%, Crud-fat 2.12%, Crude fiber 20.26%, Crude ash 15.25%, N.F.E 54.2%이었다. 3. 1975年 10월 28일 刈取한 것은 Crude protein 1.88%, Crude fat 2.61%, Crude fiber 18.45%, Crude ash 16.02%, N.F.E 55.33%이었다. The green yield and chemical composition of Tong-il rice straw which regrew after harvest were determined. No fertilizer was applied for regrowth of the rice stubble. The harvesting date of rice was September 27 and the cutting dates were October 18 and 28, 1975. The results obtained were as follows: 1. The green yield of the rice straw which regrew up to October 18 and 28 after harvest averaged 165kg/10a and 162kg/10a, respectively. 2. The chemical composition of the green straw cut on October 18 was determined as follows: 1.50% crude protein, 2.12% crude fat, 20.26% crude fiber, 15.25% crude ash and 54.24% nitrogen free extracts. 3. The chemical cpmposition of the green straw cut on October 28 was determined as follows: 1.88% crude protein, 2.61% crude fat, 18.45% crude ash and 55.33% nitrogen free extracts.

      • 智里山緬羊牧場 造成에 關한 硏究 : 第11報 : 緬羊飼育適地 細部調査 11. Further Survey for Establishing Sheep Range and Farm Groups

        鄭鉉丞 진주산업대학교 1975 論文集 Vol.13 No.-

        지리산 지역의 3개소에 대한 면양사육의 적지조사를 실시한 결과 다음과 같은 결론을 얻었다. 1. 조사한 3개소의 위치는 경남 산청군 삼장면 외곡 지역과 삼장면-금서면의 밤머리재 지역 및 시천면 순두류 지역이 었다. 해발은 400∼1,200mm 범위이었고 목야지로 이용 가능한 총 지역은 1,150ha이었으며 이중 초지조성 가능 면적은 35% 로서 450ha이었다. 2. 일반적인 기상, 토양 및 수자원 조사결과는 면양 사육이나 초생에 대하여 양호한 조건을 갖추고 있다고 판단되었다. 일반 야산지대에 비하여 토양유기물 함량은 약 4배나 높은 13.3%이었으나 계속적인 초지관리를 위하여는 3요소의 금비시비가 필요할 것이며 토양 pH는 5.5에 불과하므로 석회의 시용도 필요할 것으로 생각된다. 3. 자연야초에 대한 초자원 조사결과 새, 억새 및 기름새 등의 화본과 야초가 우점된 집단 야초지로서 1년간 20일 주기로 5회 예취한 생초수량은 3,683kg/10a에 달했다. 시비의 효과는 별로 높지 않았고 일반성분 함량도 전국의 평균치와 비슷하였다. 4. 목초재배 시험결과 8월 10일 이전에 파종함이 좋을 것으로 생각되며 오차드 그라스가 가장 내한성이 높았다. 초년도 혼파목초의 생초수량은 600∼900m 지대에서 평균 3,630kg/10a로 나타났다. 5. 야초지에서 면양사육 결과 방목기에는 농후사료의 보충급여가 필요없었으나 월동기 및 번식기에는 보충급여가 필요할 것으로 판단되었다. 이유후 15.5개월간 사육한 결과 일당 증체량은 평균 63∼65g으로 나타났다. 1세양의 산모량은 3.45∼3.43kg으로 양호한 결과라고 생각된다. 10두중3두가 요마비에 감염하여 그중 2두는 완치되었으나 1두는 폐사하였으며 기타의 질병 발생은 없었다. 6. 교통상황 조사결과 외곡지역은 진입도로 1.5km와 교량 50m, 순두류 지역은 진입도로 1.0km와 교량 50m의 개설이 필요하였으며 밤머리재 지역은 진입도로의 개설이 필요하였으며 밤머리재 지역은 진입도로의 개설이 필요없었다. 각 지역에 있어서 목도의 개설길이는 외곡 8.0km, 순두류 16.0km, 밤머리재 11.0km로 추정된다. 7. 인근부락의 농가실태 조사결과 농가는 총 242호로서 외곡지역이 가장 많고 순두류 지역은 가장 적었다. 면양사육을 위하여 필요한 유휴 노동력을 조사한 결과 순두류 지역에서만 2,000두 사육상당의 노력이 부족한 것으로 분석되었다. 이들 농가의 면양사육을 위한 자본조사 결과 총 242호 중에서 자기 자본으로 사육가능하다는 농가는 16호, 일부융자가 필요하다는 농가가 46호 뿐이며 기타는 자본의 여유가 없다고 응답하였다. 8. 면양업의 수익성 분석 결과는 본 연구자와 기타 관련 연구에서 보고된 수익성의 범위가 200두 사육 규모에서 두당 연간 수익성이 4,000∼5,000원으로 추정되며 면양업의 단지화 조성시와 가내 수공업을 병행하고 생산물의 판로 등을 조직화함 으로써 이러한 수익은 거의 100% 이상 증진시킬 수 있는 것으로 판단되어 이들 지역의 농가에서 요구하는 소득수준에 충분한 것으로 분석된다. 9. 면양사육에 대한 기술지도 및 생산물의 유통 기구의 합리적인 방안에 관하여 연구한 결과를 기술하였는데 건전한 면양업 육성을 위하여는 면양진흥연구 협의회를 구성하여 여러 문제의 해결에 적극적인 노력을 함으로써 수익성을 크게 높여야 할것으로 생각된다. 10. 3개지역 면양목장 조성시에 지역농가에 의한 단지화의 경우의 자본에 대한 조사결과 농가의 응답에 의한 자본으로는 2,000두 사육에 불과한 것으로 추정되나 기업목장을 유도하여 초지조성등 적극적인 경우는 자연 조건하에서 14,000두의 사육이 가능한 것으로 추정되었다. The natural and Social factors of three regions in Mt. Chiri were evaluated for establishment of sheep farm groups on the basis of author's previous survey and the present resurvey. The results obtained were as follows: 1. The regions surveyed were located at (1) Oegog, Samjang-myun, Sancheong-kun, (2) Bammerijae, Samjang-Geomseo-myun, Sancheong-kun, and (3) Sunduryu, Sicheon-myun, Sancheong- kun. The total area available for establishing sheep range and grassland in these regions were estimated 1, 150 ha and 450 ha, respectively. Their altitude ranged from 400 to 1,200m. 2. These regions were considered to have the relatively good meteological, soil and water resource for raising sheep and growing pastures. The organic matter content of soil(13.3%) in Oegog reging was almost 4 times as much, comparing with the results reported about most of the hilly lands in korea. However, the spplication of chemical fertilizers including lime was esssential for intensive grassland farming. The pH value of surface soil was averaged 5.5. 3. The vegetation survey showed that the dominant species of native grasses were Arundinella hirta, Miscanthus Sinensis and Eccoilopus cotulitfer. The green yield of native grasses from 5 cuttings with interval of 20 days was averaged 3,683kg/10a. The productivity of native grasses was not inproved greatly by the fertilizers application at least for the first year. The chemical composition pf native grasses in this region was comparable to the over-all country average reported. 4. In the fall-sowing system of Pasture it was considered that the best winter survival resulted from the sowing at earlier than August 10 and orchard grass showed the highest winter survival of the 4 species of pasture examined. The green yield of the mixed pasture of orchard grass, tall fescue and ladino clover was averaged 3,630kg/10a for the first establishment year. 5. The supplement feeding of concentrates to ewes on these native grasslands was considered effective only in the dry-lot feeding for the increase in body gain and in the early breeding season for the inprovement in lamb crops. The average postweaning daily gain of ewes on the native grasslands with or without supplements was 63 to 65 g for the period of 15.5 months. The average fleece yield of yearling ewes on the native grasslands with or without supplements were 3.45 to 3.43kg. Three of 10ewes used showed the symptoms of Lumbar paralysis from which one of them was died and the others were recovered by treaement. No other disease troubles were observed in the ewes for the experimental period. 6. The region of Bammerijae was introduced by the established roadway. But the other two regions were located at intervals of 1.5km in Oegog and 1.0km in Sunduryu from rodway. and both the regions required a bridge to span the river of about 50 m wide. Requirements of within-range pathway or roadway to be established for these regions were estimated 8km in Oegog, 16km in Sunduryu and 11km in Bammerijae. 7. A total of 242 farm households were distributed near these regions with relatively more in Oegog and less in Sunduryu. The labor resource survey showed that the lack of unemployed near-by farm man-power limited the sheep population of about 2,000 heads only in sunduryu. According to the answers of near-by farms the capital resource available for sheep production was very poor. The requirement of loan from the Government was none in 16 farms,partial in 46 farms and full in the others. 8. From the income analysis for sheep production by the previous authors and other reports, the annual net income per head in the flock size of 200 heads per farm was estimated 4,000 to 5,000 won. such a income was con-sidered to be increased at least twice as much by the grouping of sheep farms, domestic wool processing, improved products disposal system and etc. The level of income estimated was considered enough to meet the requirement of neer-by farms. 9. A suggestion to the technical extension system and wool marketing system was made. A sheep production development council by the Government officers, animal scientists and leading farmers concerning in sheep production was suggested to be made up and to solve the various problems in the profit increase of sheep industry. 10. The available capital resource of near-by farms was enough to keep the flock of 2,000 heads only in these regions. However, it was estimated that the natural resources including labor-power in these regions allowed the sheep production of 14,000 heads on the intensively established grasslands.

      • Seed-mediated synthesized FER for dimethyl ether carbonylation to methyl acetate

        정현승,함형원,박경수,배종욱 한국공업화학회 2018 한국공업화학회 연구논문 초록집 Vol.2018 No.0

        Dimethyl ether (DME) can be utilized to produce methyl acetate (MA) by carbonylation of DME, which can be transformed to ethanol or acetic acid through a subsequent hydrogenation or hydration reaction. To insert the carbon monoxide into the DME, zeolite can be used as a heterogeneous catalyst since its acidic sites can efficiently form methoxy and acetyl intermediates from the adsorbed DME and CO molecules. Nowadays, the seed-derived ferrierite (FER) was investigated to observe the effects of crystallinity and acidic natures to catalytic activity and stability. Seed-mediated synthesis of FER was applied using an as-synthesized FER as a seeding material to tune the crystallinity of the final FER zeolite at different seed concentration. A pristine FER and seed-mediated FER were tested for DME carbonylation, and the FER seed contents were optimized to find out the best catalyst by showing a higher stability originated from a less deposition of coke precursors during DME carbonylation.

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