Gastroesophageal reflux disease (GERD) is a condition that develops when the reflux of gastric contents into the esophagus leads to troublesome symptoms and/or complications. Heartburn is the cardinal symptom, often a...Gastroesophageal reflux disease (GERD) is a condition that develops when the reflux of gastric contents into the esophagus leads to troublesome symptoms and/or complications. Heartburn is the cardinal symptom, often associated with regurgitation. In patients with endoscopy-negative heartburn refractory to proton pump inhibitor (PPI) therapy and when the diagnosis of GERD is in question, direct reflux testing by impedance-pH monitoring is warranted. Laparoscopic fundoplication is the standard surgical treatment for GERD. It is highly effective in curing GERD with a 80% success rate at 20-year follow-up. The Nissen fundoplication, consisting of a total (360°) wrap, is the most commonly performed antireflux operation. To reduce postoperative dysphagia and gas bloating, partial fundoplications are also used, including the posterior (Toupet) fundoplication, and the anterior (Dor) fundoplication. Currently, there is consensus to advise laparoscopic fundoplication in PPI-responsive GERD only for those patients who develop untoward side-effects or complications from PPI therapy. PPI resistance is the real challenge in GERD. There is consensus that carefully selected GERD patients refractory to PPI therapy are eligible for laparoscopic fundoplication, provided that objective evidence of reflux as the cause of ongoing symptoms has been obtained. For this purpose, impedance-pH monitoring is regarded as the diagnostic gold standard.展开更多
Raw materials have a signcant influence on the qu.ality of the final refractory products, as the crude ore often comes for processing with significant variations in chemical and mineralogical composition. Therefore, i...Raw materials have a signcant influence on the qu.ality of the final refractory products, as the crude ore often comes for processing with significant variations in chemical and mineralogical composition. Therefore, it is necessary to guarantee the stable quality of raw materials with pre-assigned qualitative factors. It is possible to solve these problems by separating raw materials by grades, including the rejection of the portions of material unsuitable for specific application, and by reasonable control of the processing parameters based on real-time infirmation about chemical composition of raw materials. This can be effectively achieved by MAYA laser ele- mental analyzers based on LIBS. Being applied in ex traction, beneficiation and processing of the mineral raw materials, LIBS analyzers can be used for automatic sor ting ＂ the ore extracted or crushed and automatic dosage of components to stabilize the composition of raw material mixtures.展开更多
Calcium hexaluminate is one from such perspective materials. It is characterized by high refractoriness （ above 1 830 ~C ） , as well as properties stability in reducing atmosphere, high alkali- and slag-resistance...Calcium hexaluminate is one from such perspective materials. It is characterized by high refractoriness （ above 1 830 ~C ） , as well as properties stability in reducing atmosphere, high alkali- and slag-resistance, low thermal conductivity and wettability by molten metals. In this work influence researches of fused calcium hexaluminate material additive in amount of 5%, 15% amt 25% on the main properties of alumina refractories were carried out. It is established that, the refractories containing the additive of 25% calcium hexaluminate material are characterized by the highest properties, slightly impregnated with metal melt and the highest metal corrosion resistance. The alumina purging plugs fi）r blowing of metal with calcium hexaluminate material additive are produced and intended to one metallurgical plant of Ukraine for carrying out tests.展开更多
Al-containing low carbon MgO - C refractories were prepared using 70% （in mass, the same hereinafter） fused magnesia （ ≤3 mm）, 24% fused magnesia powder （ 〈0. 074 mm） , 3% flake graphite, 3% Al powder and 4% p...Al-containing low carbon MgO - C refractories were prepared using 70% （in mass, the same hereinafter） fused magnesia （ ≤3 mm）, 24% fused magnesia powder （ 〈0. 074 mm） , 3% flake graphite, 3% Al powder and 4% phenolic resin （extra-added） as the basic formulation. Influence of ZnO addhion on oxidation resistance of the materials was investigated by adding 1% ZnO to substitute fused magnesia powder. The relationship between in-situ formed spinel and ZnO in the matrix was discussed by comparing apparent porosity, cold crushing strength, and phase evolution of the materials matrix. The oxidation resistances of the two materials were compared by observing the formed dense MgO layer between the decarburized layer and the original layer. The result shows that adding ZnO in MgO - C refractories accelerates the in-situ formation of ZnAl204 spinel and the formation of dense MgO layer, thus improves the oxidation resistance of the low carbon MgO - C refractories.展开更多
文摘Gastroesophageal reflux disease (GERD) is a condition that develops when the reflux of gastric contents into the esophagus leads to troublesome symptoms and/or complications. Heartburn is the cardinal symptom, often associated with regurgitation. In patients with endoscopy-negative heartburn refractory to proton pump inhibitor (PPI) therapy and when the diagnosis of GERD is in question, direct reflux testing by impedance-pH monitoring is warranted. Laparoscopic fundoplication is the standard surgical treatment for GERD. It is highly effective in curing GERD with a 80% success rate at 20-year follow-up. The Nissen fundoplication, consisting of a total (360°) wrap, is the most commonly performed antireflux operation. To reduce postoperative dysphagia and gas bloating, partial fundoplications are also used, including the posterior (Toupet) fundoplication, and the anterior (Dor) fundoplication. Currently, there is consensus to advise laparoscopic fundoplication in PPI-responsive GERD only for those patients who develop untoward side-effects or complications from PPI therapy. PPI resistance is the real challenge in GERD. There is consensus that carefully selected GERD patients refractory to PPI therapy are eligible for laparoscopic fundoplication, provided that objective evidence of reflux as the cause of ongoing symptoms has been obtained. For this purpose, impedance-pH monitoring is regarded as the diagnostic gold standard.
文摘Raw materials have a signcant influence on the qu.ality of the final refractory products, as the crude ore often comes for processing with significant variations in chemical and mineralogical composition. Therefore, it is necessary to guarantee the stable quality of raw materials with pre-assigned qualitative factors. It is possible to solve these problems by separating raw materials by grades, including the rejection of the portions of material unsuitable for specific application, and by reasonable control of the processing parameters based on real-time infirmation about chemical composition of raw materials. This can be effectively achieved by MAYA laser ele- mental analyzers based on LIBS. Being applied in ex traction, beneficiation and processing of the mineral raw materials, LIBS analyzers can be used for automatic sor ting ＂ the ore extracted or crushed and automatic dosage of components to stabilize the composition of raw material mixtures.
文摘Calcium hexaluminate is one from such perspective materials. It is characterized by high refractoriness （ above 1 830 ~C ） , as well as properties stability in reducing atmosphere, high alkali- and slag-resistance, low thermal conductivity and wettability by molten metals. In this work influence researches of fused calcium hexaluminate material additive in amount of 5%, 15% amt 25% on the main properties of alumina refractories were carried out. It is established that, the refractories containing the additive of 25% calcium hexaluminate material are characterized by the highest properties, slightly impregnated with metal melt and the highest metal corrosion resistance. The alumina purging plugs fi）r blowing of metal with calcium hexaluminate material additive are produced and intended to one metallurgical plant of Ukraine for carrying out tests.
文摘Al-containing low carbon MgO - C refractories were prepared using 70% （in mass, the same hereinafter） fused magnesia （ ≤3 mm）, 24% fused magnesia powder （ 〈0. 074 mm） , 3% flake graphite, 3% Al powder and 4% phenolic resin （extra-added） as the basic formulation. Influence of ZnO addhion on oxidation resistance of the materials was investigated by adding 1% ZnO to substitute fused magnesia powder. The relationship between in-situ formed spinel and ZnO in the matrix was discussed by comparing apparent porosity, cold crushing strength, and phase evolution of the materials matrix. The oxidation resistances of the two materials were compared by observing the formed dense MgO layer between the decarburized layer and the original layer. The result shows that adding ZnO in MgO - C refractories accelerates the in-situ formation of ZnAl204 spinel and the formation of dense MgO layer, thus improves the oxidation resistance of the low carbon MgO - C refractories.
