• 제목/요약/키워드: partial replacement

검색결과 332건 처리시간 0.023초

프리팩트 폴리머 시멘트 콘크리트용 주입 폴리머 시멘트 모르터의 성질에 관한 연구 (A Study on Basic Properties of Grouting Motars for polymer-Modified preplaced Aggregate Concrete)

  • 이철웅;김완기;조영국;소양섭
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1998년도 가을 학술발표논문집(II)
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    • pp.350-355
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    • 1998
  • Preplaced aggregate concrete in the building fields has recently been used in the partial repair works for damaged reinforced concrete structures, and polymer-modified mortars have been employed as grouting mortars for the preplaced aggregate concrete. The objective of this study is to clear the properties of polymer-modified grouting mortars. Polymer-modified mortars using a polystyrene acrylic(St/Ac) emulsion as grouting mortars for preplaced aggregate concrete are prepared with various mix proportions, and tested for flexural and compressive strengths, adhesion in tension. The flexural strength of emulsion-modified grouting mortars does not give much variation with increasing fly ash replacement for cement and sand-binder ratio. With increasing polymer-binder ratio, the flexural strength and adhesion in tension of St/Ac emulsion-modified grouting mortars increases, become nearly constant or reaches a maximum at a polymer-binder ratio of 5%. From the test results, St/Ac emulsion-modified grouting mortar with a polymer-binder ratio of 5%, a fly ash replacement of 10% for cement and sand-binder ratio of 1.0 is recommended as a grouting mortar for preplaced aggregate concrete.

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Etched Metal Resin Bonded Retainer에 관한 임상적 연구 (A Clinical Study on the Etched Resin Bonded Retainer for Fixed Bridgework)

  • 양재호
    • 대한치과의사협회지
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    • 제21권5호통권168호
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    • pp.395-402
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    • 1983
  • The purpose of this study was to apply the etched metal ceramometal retainer using a composite resin and acid-etch procedure with minimal tooth reduction of abutments for the replacement of one missing anterior or posterior tooth. Author obtained the following conclusions. 1. conservation of tooth structure and minimal chair time and patient expense were the primary advantages of etched metal retainer. 2. This fixed partial denture permitted good esthetic results. 3. This retainer was successfully applied for the replacement of one missing anterior or posterior tooth. 4. Proper retainer etching ws an important procedure. 5. Etched castings could be applied to periodontal splinting and post orthodontic fixation.

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Partial replacement of fine aggregates with laterite in GGBS-blended-concrete

  • Karra, Ram Chandar;Raghunandan, Mavinakere Eshwaraiah;Manjunath, B.
    • Advances in concrete construction
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    • 제4권3호
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    • pp.221-230
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    • 2016
  • This paper presents a preliminary study on the influence of laterite soil replacing conventional fine aggregates on the strength properties of GGBS-blended-concrete. For this purpose, GGBS-blended-concrete samples with 40% GGBS, 60% Portland cement (PC), and locally available laterite soil was used. Laterite soils at 0, 25, 50 and 75% by weight were used in trails to replace the conventional fine aggregates. A control mix using only PC, river sand, course aggregates and water served as bench mark in comparing the performance of the composite concrete mix. Test blocks including 60 cubes for compression test; 20 cylinders for split tensile test; and 20 beams for flexural strength test were prepared in the laboratory. Results showed decreasing trends in strength parameters with increasing laterite content in GGBS-blended-concrete. 25% and 50% laterite replacement showed convincing strength (with small decrease) after 28 day curing, which is about 87-90% and 72-85% respectively in comparison to that achieved by the control mix.

개심술후 발생한 일측성 성대마비 -2례 보고- (Unilateral vocal cord paralysis after open heart surgery -A report of 2 cases-)

  • 이종욱
    • Journal of Chest Surgery
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    • 제23권3호
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    • pp.522-526
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    • 1990
  • We have experienced 2 cases vocal cord paralysis after open heart surgery. One was a postoperatively developed right unilateral vocal cord paralysis after prosthetic mitral valve replacement with tricuspid valve annuloplasty. The other was a postoperative left unilateral vocal cord paralysis after prosthetic aortic and mitral valve replacement with tricuspid annuloplasty. They were intubated for forty-eight and seventy-two hours but after extubation complained of hoarseness, aphonia, anxiety, and ineffective coughing Indirect laryngoscopy performed at about postoperative one week, revealed partial paralysis and decreased mobility of the vocal cord. After active phonation therapy, symptoms were improved gradually and in the follow up indirect laryngoscopy, the vocal cord paralysis was improved. The symptoms were recovered completely at about postoperative one month in both. The cause of vocal cord paralysis after open heart surgery may be any retraction or stretching injury to the recurrent laryngeal nerve, especially right side, during median sternotomy retraction and open heart operation procedures. As a result, avoid of excessive spread of median sternotomy retractor and excessive manipulation and retraction of the heart during open heart procedures will reduce the occurrence of the vocal cord paralysis.

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Flexural studies on reinforced geopolymer concrete beams under pure bending

  • Sreenivasulu, C.;Jawahar, J. Guru;Sashidhar, C.
    • Advances in concrete construction
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    • 제8권1호
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    • pp.33-37
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    • 2019
  • The present investigation is mainly focused on studying the flexural behavior of reinforced geopolymer concrete (RGPC) beams under pure bending. In this study, copper slag (CS) was used as a partial replacement of fine aggregate. Sand and CS were blended in different proportions (100:0, 80:20, 60:40 and 40:60) (sand:CS) by weight. Fly ash and ground granulated blast furnace slag (GGBS) were used as binders and combination of sodium hydroxide (8M) and sodium silicate solution were used for activating the binders. The reinforcement of RGPC beam was designed as per guidelines given in the IS 456-2000 and tested under pure bending (two-point loading) after 28 days of ambient curing. After conducting two point load test the flexural parameters viz., moment carrying capacity, ultimate load, service load, cracking moment, cracking load, crack pattern and ultimate deflection were studied. From the results, it is concluded that RGPC beams have shown better performance up to 60% of CS replacement.

Investigation towards strength properties of ternary blended concrete

  • Imam, Ashhad;Moeeni, Shahzad Asghar;Srivastava, Vikas;Sharma, Keshav K
    • Advances in concrete construction
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    • 제11권3호
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    • pp.207-217
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    • 2021
  • This study relates to a production of Quaternary Cement Concrete (QCC) prepared by using Micro Silica (MS), Marble Dust (MD) and Rice Husk Ash (RHA), followed by an investigation towards fresh and hardened properties of blended concrete. A total of 39 mixes were cast by incorporating different percentages of MS (6%, 7% and 8%), MD (5%, 10% and 15%) and RHA (5%, 10%, 15% and 20%) as partial replacement of Ordinary Portland Cement. The workability of fresh concrete was maintained in the range of 100±25 mm by adding 0.7% of Super Plasticizer in the mix. Optimum mechanical strength was observed at combination of 8% MS+5% MD+10% RHA. Marble dust replacement from 10 to 15% and Rice husk ash replacements from 15 to 20% depicted a substantial reduction in compressive strength at all ages. Durability parameter with respect to water absorption at 28 days shows an increasing trend as the percentage of blending increases.

Effects of Additives on Laying Performance, Metabolic Profile, and Egg Quality of Hens Fed a High Level of Sorghum (Sorghum vulgare) during the Peak Laying Period

  • Imik, H.;Hayirli, A.;Turgut, L.;Lacin, E.;Celebi, S.;Koc, F.;Yildiz, L.
    • Asian-Australasian Journal of Animal Sciences
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    • 제19권4호
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    • pp.573-581
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    • 2006
  • This experiment was conducted to determine the effects of supplemental methionine, lysine, choline, and sulfur on laying performance, metabolic parameters, and egg quality of hens fed diets containing sorghum (Sorghum vulgare) during the peak laying period. Lohman layers (n = 144), 30-wk of age as 6 replicate cages of 4 hens, were allocated randomly to receive basal diets containing either 22% corn (B) or 22% sorghum (BS) and diets BS plus 0.57% methionine, 0.66% lysine, 0.47% choline, or 0.05% sulfur for 98 d. Feed intake (FI) and egg production (EP) were recorded daily, egg weight (EW) was measured bi-weekly, and body weight (BW) was measured monthly. A sample of 12 eggs from each experimental group was collected every month to evaluate egg quality. At the end of the experiment, blood samples were collected for metabolite concentrations. Data were analyzed using one-way ANOVA as repeated measures and significant differences between the experimental groups were assessed using Duncan's Multiple Range test. Partial replacement of corn with sorghum in the basal diet did not affect BW, EP, and FCR but increased FI by 5.7% and EW by 2.4%. The effects of additives on laying performance were variable. Except for serum total protein (STP) concentration, other metabolic parameters were not affected by partial replacement of corn with sorghum in the basal diet. Hens fed diet BS had lower SPT concentration than hens fed diet B. Except for methionine supplementation, other supplements ameliorated depression in STP concentration. The additives did not affect other metabolic parameters. Egg quality responses to the experimental diets were also variable. Partial replacement of corn with sorghum in the basal diet did not affect eggshell characteristics (both thickness and stiffness), whereas it had variable effects on inner egg quality parameters (increased yolk index, depressed yolk color, and unaltered albumen index and Haugh unit). In conclusion, laying hen diets could include low-tannin sorghum (0.26%) up to 22% without necessitating extra supplements to overcome compromised performance.

The Nutritive Value of Mulberry Leaves (Morus alba) and Partial Replacement of Cotton Seed in Rations on the Performance of Growing Vietnamese Cattle

  • Vu, Chi Cuong;Verstegen, M.W.A.;Hendriks, W.H.;Pham, K.C.
    • Asian-Australasian Journal of Animal Sciences
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    • 제24권9호
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    • pp.1233-1242
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    • 2011
  • The in vivo digestibility of mulberry leaves (Morus alba) and the effects of the partial replacement of cotton seed with fresh mulberry leaf in rations on the performance of growing Vietnamese cattle was investigated. For the in vivo digestibility trial, twenty castrated rams of Phanrang breed (a local prolific breed) with an initial weight of 23-25 kg, were first assigned to four groups according to weight and then randomly assigned to one of four dietary treatments to determine digestibility of nutrients in mulberry leaves (M. alba), natural Bermuda grass (Cynodon dactylon), elephant grass (Pennisetum purpureum) and buffalo grass (Panicum maximum cv. TD 58). All forages were cut and chopped daily before being offered (at 120% maintenance) to the sheep. In the feeding trial, 20 Laisind (Vietnam yellow cows${\times}$Red Sindhy bulls) crossbred bulls averaged 18 month old and 184 kg were used to investigate the effect of partial replacement of cottonseed in the diet by mulberry leaves on live weight gain and feed conversion rate. The experiment was a randomized complete block design with four levels of fresh mulberry leaves which varied from 0 to 15% of total dietary dry mater and five animals per treatment over an 84 day period. The in vivo digestion trial showed the superior quality of mulberry leaves compared with the grasses. Chemical analysis indicated that mulberry leaves had the highest CP and the lowest NDF contents (22.3 and 31.1% DM, respectively) among the four forages tested. Digestibility of DM and OM of the mulberry leaf (66.4 and 71.8%, respectively) was also the highest but that of CP (58.2%) and NDF (58.4%) was the lowest of the four forages evaluated (p<0.05). Consequently, the ME value and therefore net energy (NE) and unit feed for lactation (UFL) values of the mulberry leaves, which was estimated from chemical composition and digestibility values, were the highest among the forages investigated in the present study. Results of the feeding trial showed no treatment effect on average daily gain (ADG) of the cattle. The values were 554, 583, 565 and 568 g/d for animals in the diets of 0, 5, 10, and 15% mulberry leaves inclusion, respectively. Total DM intake of the animal was not affected by the treatment when expressed as kg/animal/d. However, when adjusted for metabolic weight of the animal the DM intake was reduced (p<0.05) as whole cottonseed was replaced by mulberry leaves in the ration. When the level of mulberry leaves in the ration increased from 5 to 15% of dietary DM at the expense of whole cottonseed, CP and ME intakes of the cattle were significantly decreased (p<0.05) and the feed to gain ratio reduced by 8 to 14% as compared with the control diet (p<0.05). Mulberry leaf is a good feed ingredient for ruminants because of its high level of crude protein and high digestibility of nutrients and energy. Mulberry leaves can be efficiently used as a source of protein supplement to replace cottonseed, a more expensive animal feeds ingredient, in the diet for Vietnamese cattle.

식도협착으로 식도부분절제술과 위간치술 후 발생한 식도암에서 시행한 전인두후두식도위적출술 및 대장치환술 치험 1예 (A Case of Total Pharyngo-laryngo-esophagogastrectomy and Colon Transposition in a Patient with Esophageal Cancer following Partial Esophagectomy and Gastic Pull-up due to Esophageal Stricture)

  • 왕수건;손봉형;이병주;이형렬
    • 대한기관식도과학회지
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    • 제9권2호
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    • pp.69-73
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    • 2003
  • Various flaps are using for reconstruction of esophageal defect. The choice of reconstruction is depended to the oncologic needs of the situation. If the entire esophagus or significant part of the thoracic esophagus is involved by tumor, then total esophagectomy and gastric pull-up or colon transposition is indicated. But for most hypopharyngeal tumors, laryngopharyngeal tumors, and cervical esophageal tumors, segmental resection of these area and replacement with a jejunal fee or forearm free flap has become the standard technique. The authors have experienced a case of total pharyngo-laryngo-esophago-gastrectomy and colon transposition in a patient of esophageal cancer following partial esophagectomy and gastic pull-up due to corrosive esophageal stricture. We report this case with brief review of the literatures.

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기관지 압박을 초래한 만성 해리성 대동맥류(Type B) -임상적 치험 1례- (Tracheal Compression by Xhronic Dissecting Aeurysm(TYpe B) -A Case Report-)

  • 송정근
    • Journal of Chest Surgery
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    • 제28권3호
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    • pp.328-331
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    • 1995
  • A 42-year-old Marfan female had a chronic dissection of the descending aorta[Type B and the aneurysmal expansion of the descending aorta caused compression of the trachea resulting in respiratory distress which mimicked bronchial asthma. The patient has been successfully managed by resection and replacement of the aneurysm in the descending aorta. The operation could be done without the aid of the partial cardiopumonary bypass. As the patient had been prepared by unilateral axillo-bifemoral by-pass using prosthetic graft 8mm in diameter 10days prior to the main operation.

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