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Asymptomatic low-grade appendiceal mucinous neoplasm:A case report
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作者 Min-Quan Yao Yu-Peng Jiang +2 位作者 Yuan-Yu Wang Yi-Ping Mou Jin-Xing Fan 《World Journal of Clinical Cases》 SCIE 2024年第2期361-366,共6页
BACKGROUND Low-grade appendiceal neoplasms(LAMN)are characterized by low incidence and atypical clinical presentations,often leading to misdiagnosis as acute or chronic appendicitis before surgery.The primary diagnost... BACKGROUND Low-grade appendiceal neoplasms(LAMN)are characterized by low incidence and atypical clinical presentations,often leading to misdiagnosis as acute or chronic appendicitis before surgery.The primary diagnostic tool for LAMN is abdominal computed tomography(CT)imaging.Surgical resection remains the cornerstone of LAMN management,necessitating en bloc tumor excision to minimize the risk of iatrogenic rupture.Laparoscopy,known for its minimal invasiveness,reduced postoperative discomfort,and expedited recovery,is a safe and reliable approach for LAMN treatment.Despite the possibility of pseudomyxoma peritonei development,appendectomy and partial appendectomy generally result in negative tumor margins and favorable outcomes,which can be attributed to the disease’s slow growth and lower malignancy.CASE SUMMARY A 71-year-old male patient was admitted to our hospital with a pelvic spaceoccupying lesion detected 1 mo prior.Physical examination showed a soft abdomen without tenderness or rebound and no palpable masses.No shifting dullness was noted,and digital rectal examination revealed no palpable mass.Enteroscopy revealed a raised,smooth-surfaced mass measuring 3.0 cm in the cecum.Abdominal contrast-enhanced CT showed a markedly thickened and dilated appendix with visible cystic shadows.Laparoscopic surgery was performed and revealed a significantly dilated appendix,leading to laparoscopic resection of the appendix and part of the cecum.Post-surgical pathologic analysis confirmed LAMN.The patient received symptomatic and supportive post-operative care and was discharged on postoperative day 4 without complications such as abdominal bleeding,intestinal obstruction,or incision infection.No tumor recurrence was observed during a 7-mo follow-up period.CONCLUSION LAMN is a rare disease that lacks specific clinical manifestations.Abdominal CT plays a crucial role in diagnosing LAMN,and laparoscopic surgery is a safe and effective diagnostic and therapeutic approach. 展开更多
关键词 low-grade appendiceal mucinous neoplasm Pseudomyxoma peritonei Computed tomography Laparoscopy APPENDECTOMY Case report
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Low-grade myofibrosarcoma of the maxillary sinus:Two case reports
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作者 Anna Mydlak ŁukaszŚcibik +4 位作者 Monika Durzynska Jakub Zwoliński Karolina Buchajska Olga Lenartowicz Jakub Kucharz 《World Journal of Clinical Oncology》 2024年第4期566-575,共10页
BACKGROUND Low-grade myofibroblastic sarcoma(LGMS)is an extremely rare tumor characterized by the malignant proliferation of myofibroblasts.LGMS most commonly develops in adults,predominantly in males,in the head and ... BACKGROUND Low-grade myofibroblastic sarcoma(LGMS)is an extremely rare tumor characterized by the malignant proliferation of myofibroblasts.LGMS most commonly develops in adults,predominantly in males,in the head and neck region,oral cavity,especially on the tongue,mandible,and larynx.This article presents 2 cases of LGMS localized to the maxillary sinus and provides an overview of the available literature.CASE SUMMARY Two patients with LGMS located in the maxillary sinus underwent surgery at the Department of Head and Neck Surgery.Case 1:A 46-year-old patient was admitted to the clinic with suspected LGMS recurrence in the right maxillary sinus(rT4aN0M0),with symptoms of pain in the suborbital area,watering of the right eye,thick discharge from the right nostril,and augmented facial asymmetry.After open biopsy-confirmed LGMS,the patient underwent expanded maxillectomy of the right side with immediate palate reconstruction using a microvascular skin flap harvested surgically from the middle arm.The patient qualified for adjuvant radiotherapy for the postoperative bed,with an additional margin.Currently,the patient is under 1.5 years of observation with no evidence of disease.Case 2:A 45-year-old man was admitted to our clinic with facial asymmetry,strabismus,exophthalmos,and visual impairment in the right eye.Six months earlier,the patient had undergone partial jaw resection at another hospital for fibromatosis.A contrast-enhanced computed tomography scan revealed a tumor mass in the postoperative log after an earlier procedure.An open biopsy confirmed lowgrade fibrosarcoma(rT4aN0M0).The patient qualified for an extended total right maxillectomy with orbital excision and right hemimandibulectomy with immediate microvascular reconstruction using an anterolateral thigh flap.The patient subsequently underwent adjuvant radiotherapy to the postoperative area.After 9 months,recurrence occurred in the right mandibular arch below the irradiated area.The lesion infiltrated the base of the skull,which warranted the withdrawal of radiotherapy and salvage surgery.The patient qualified for palliative chemotherapy with a regimen of doxorubicin+dacarbazine+cyclophosphamide and palliative radiotherapy for bone metastases.The patient died 26 months after surgical treatment.The cases have been assessed and compared with cases in the literature.CONCLUSION No specific diagnostic criteria or treatment strategies have been developed for LGMS.The treatment used for LGMS is the same as that used for sinonasal cancer radical tumor excision;adjuvant radiotherapy or chemoradiotherapy should also be considered.They have low malignant potential but are highly invasive,tend to recur,and metastasize to distant sites.Patients should undergo regular follow-up examinations to detect recurrence or metastasis at an early stage.Patients should be treated and observed at the highest referral centers. 展开更多
关键词 Head and neck cancer Paranasal sinuses Maxillary sinus SARCOMA low-grade myofibroblastic sarcoma Case report
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Thermally Chargeable Proton Capacitor Based on Redox-Active Effect for Energy Storage and Low-Grade Heat Conversion
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作者 Yufeng An Zhiwei Li +4 位作者 Yao Sun Zhijie Chen Jiangmin Jiang Hui Dou Xiaogang Zhang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第1期384-391,共8页
Thermal energy is abundantly available in our daily life and industrial production,and especially,low-grade heat is often regarded as a byproduct.Collecting and utilizing this ignored energy by low-cost and simple tec... Thermal energy is abundantly available in our daily life and industrial production,and especially,low-grade heat is often regarded as a byproduct.Collecting and utilizing this ignored energy by low-cost and simple technologies may become a smart countermeasure to relieve the energy crisis.Here,a unique device has been demonstrated to achieve high value-added conversion of low-grade heat by introducing redox-active organic alizarin(AZ)onto N-doped hollow carbon nanofibers(N–HCNF)surface.As-prepared N–HCNF/AZ can deliver a high specific capacitance of 514.3 F g^(-1)(at 1 A g^(-1))and an outstanding rate capability of 60.3%even at 50 A g^(-1).Meanwhile,the assembled symmetric proton capacitor can deliver a high energy density of 28.0 Wh kg^(-1) at 350.0 W kg^(-1) and a maximum power density of 35.0 kW kg^(-1) at 17.0 Wh kg^(-1).Significantly,the thermally chargeable proton capacitors can attain a surprisingly high Seebeck coefficient of 15.3 mV K^(-1) and a power factor of 6.02µW g^(-1).Taking advantage of such high performance,a satisfying open-circuit voltage of 481.0 mV with a temperature difference of 54 K is achieved.This research provides new insights into construction of high value-added energy systems requiring high electrochemical performances. 展开更多
关键词 capacitors low-grade heat redox-active effect thermal chargeability
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Anlotinib in combination with pembrolizumab for low-grade myofibroblastic sarcoma of the pancreas: A case report
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作者 Rong-Ting Wu Ji-Cheng Zhang +4 位作者 Cheng-Nan Fang Xiao-Yu Qi Jin-Fei Qiao Ping Li Li Su 《World Journal of Clinical Cases》 SCIE 2023年第35期8385-8391,共7页
BACKGROUND Low-grade myofibroblastic sarcoma(LGMS)is a rare spindle cell sarcoma espe-cially in the pancreas,with myofibroblastic differentiation.Hitherto,only a few cases have been reported.CASE SUMMARY Herein,we rep... BACKGROUND Low-grade myofibroblastic sarcoma(LGMS)is a rare spindle cell sarcoma espe-cially in the pancreas,with myofibroblastic differentiation.Hitherto,only a few cases have been reported.CASE SUMMARY Herein,we report a case involving the discovery of a pancreatic mass detected during a routine physical examination.Subsequent imaging and pathological tests of the patient led to the diagnosis of LGMS of the pancreas.Following surgical intervention,the patient experienced recurrence and metastasis.Conventional treatment is not effective for postoperative recurrent pancreatic LGMS with multiple metastases.After communicating with the patients and their families,informed consent was obtained for the treatment of anlotinib combined with pembrolizumab.Evaluation of imaging and clinical symptoms post-treatment revealed a relatively favorable response to the combination of anlotinib and pembrolizumab.CONCLUSION Based on the comprehensive literature review,our report aimed to provide evidence for a better understanding of the disease characteristics,diagnostic criteria,imaging findings,and identification of LGMS.And explore novel treatment strategies for this disease. 展开更多
关键词 low-grade myofibroblastic sarcoma PANCREAS Pembrolizumab Anlotinib IMMUNOHISTOCHEMISTRY PATHOLOGY Case report
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Thermal expansion of kyanite at ambient pressure:An X-ray powder diffraction study up to 1000℃ 被引量:11
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作者 Xi Liu Qiang He +2 位作者 Hejing Wang Michael E. Fleet Xiaomin Hu 《Geoscience Frontiers》 SCIE CAS 2010年第1期91-97,共7页
The thermal expansion coefficients of kyanite at ambient pressure have been investigated by an X-ray powder diffraction technique with temperatures up to 1000 ℃. No phase transition was observed in the experimental t... The thermal expansion coefficients of kyanite at ambient pressure have been investigated by an X-ray powder diffraction technique with temperatures up to 1000 ℃. No phase transition was observed in the experimental temperature range. Data for the unit-cell parameters and temperatures were fitted empirically resulting in the following thermal expansion coefficients: αa = 5.8(3) × 10^-5, αb = 5.8 (1)× 10^-5, αc = 5.2(1)× 10^-5, and αv = 7.4(1) × 10^-3 ℃ 1 in good agreement with a recent neutron powder diffraction study. On the other hand, the variation of the unit-cell angles α, β and γ of kyanite with increase in temperature is very complicated, and the agreement among all studies is poor. The thermal expansion data at ambient pressure reported here and the compression data at ambient temperature from the literature suggest that, for the kyanite lattice, the most and least thermally expandable directions correspond to the most and least compressible directions, respectively. 展开更多
关键词 High temperature kyanite Thermal expansion X-ray powder diffraction
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Sillimanite,Kyanite and Andalusite in China and Their Applications Part Ⅰ:Their Reserve,Distribution and Characteristics 被引量:5
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作者 LINBinyin LIUJiehua +1 位作者 ZHOUNingsheng WANGJianiun 《China's Refractories》 CAS 2003年第3期13-18,共6页
Sillimanite, kyanite and andalusite are advantageous natural refractory raw materials for aluminosilicate refractories to attain improved key properties. This paper are divided into two parts to introduce their resour... Sillimanite, kyanite and andalusite are advantageous natural refractory raw materials for aluminosilicate refractories to attain improved key properties. This paper are divided into two parts to introduce their resource and technical characteristic in the first part, and their applications in refractories in the second part to be succeeded . In this part, based on authors ' knowledge and sources , information on their reserve, distribution, composition and characteristic is provided , to bring it to light that China is rich in the reserve of them , in particular andalusite. The sillimanite group minerals are characterized by their phase transformation to form primary mullite and secondary mullite when added in high alumina system , accompanied by volume expansion , which can be taken use to improve creep resistances and thermal shock resistance of the related refractories. 展开更多
关键词 SILLIMANITE kyanite ANDALUSITE Re- serve DISTRIBUTION CHARACTERISTICS Refractories
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Hepatic steatosis,low-grade chronic inflammation and hormone/growth factor/adipokine imbalance 被引量:24
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作者 Giovanni Tarantino Silvia Savastano Annamaria Colao 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第38期4773-4783,共11页
Non-alcoholic fatty liver disease (NAFLD), a further expression of metabolic syndrome, strictly linked to obesity and diabetes mellitus, is characterized by insulin resistance (IR), elevated serum levels of free fatty... Non-alcoholic fatty liver disease (NAFLD), a further expression of metabolic syndrome, strictly linked to obesity and diabetes mellitus, is characterized by insulin resistance (IR), elevated serum levels of free fatty acids and fatty infi ltration of the liver, which is known as hepatic steatosis. Hepatocyte apoptosis is a key feature of this disease and correlates with its severity. Free-fatty-acidinduced toxicity represents one of mechanisms for the pathogenesis of NAFLD and hormones, growth factors and adipokines influence also play a key role. This review highlights the various pathways that contribute to the development of hepatic steatosis. Circulating concentrations of inflammatory cytokines are reckoned to be the most important factor in causing and maintaining IR. Low-grade chronic inflammation is fundamental in the progression of NAFLD toward higher risk cirrhotic states. 展开更多
关键词 Hepatic steatosis low-grade chronic inflammation ADIPOKINES HORMONES Growth factors
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The Lanshantou Kyanite-bearing Eclogite with Coesite Inclusions in the Sulu Ultrahigh-Pressure Metamorphic Belt and Its PTt Path 被引量:5
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作者 HU Shouxi, SUN Jinggui, LING Hongfei, YE Ying, Fang Changquan and ZHAO Yiying Department of Earth Sciences, Nanjing University, Nanjing 210008, Jiangsu Department of Earth Sciences, Zhejiang University, Hangzhou 310027, Zhejiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2001年第4期409-420,共12页
Coesite inclusions are found in kyanite from the Lanshantou eclogite in the Sulu ultrahigh-pressure (UHP) metamorphic belt. This discovery extends the stable region of kyanite to over 2.4 GPa. As an important UHP meta... Coesite inclusions are found in kyanite from the Lanshantou eclogite in the Sulu ultrahigh-pressure (UHP) metamorphic belt. This discovery extends the stable region of kyanite to over 2.4 GPa. As an important UHP metamorphic belt in China, the Sulu eclogite belt is the product of A-subduction induced by strong compression of the Yellow Sea terrane to the Jiaodong-northereastern Jiangsu terrane during the interaction of the Eurasian plate and Palaeo-Pacific plate in the Indosinian. It stretches about 350 km and contains over 1000 eclogite bodies. Most eclogites in this belt belong to Groups B and C in the classification of Coleman et al., and commonly contain kyanite, while the Lanshantou eclogite belongs to Group A and contains coesite. The MgO, CaO and FeO contents in garnet and pyroxene show regular variation from the core to the rim, which reveals the PTt paths of progressive metamorphism during the Early Mesozoic (240-200 Ma) and retrogressive metamorphism during the Late Mesozoic and Cenozoic exhumation. 展开更多
关键词 coesite-bearing kyanite eclogite ultrahigh-pressure (UHP) metamorphic belt PTt path of subduction and exhumation
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Low-grade myofibroblastic sarcoma of the palate 被引量:11
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作者 Tomohiro Yamada Tomohide Yoshimura +3 位作者 Naoya Kitamura Eri Sasabe Seiji Ohno Tetsuya Yamamoto 《International Journal of Oral Science》 SCIE CAS CSCD 2012年第3期170-173,共4页
Low-grade myofibroblastic sarcoma (LGMS) is a rare, malignant tumor with myofibroblastic differentiation. Despite it being classified as a distinct entity by the World Health Organization, a few cases were reported ... Low-grade myofibroblastic sarcoma (LGMS) is a rare, malignant tumor with myofibroblastic differentiation. Despite it being classified as a distinct entity by the World Health Organization, a few cases were reported in the oral and maxillofacial region. Here, a LGMS developed on the palate of a 73-year-old man who presented with a 1-cm tumor on the posterior border of the palate. Based on the histological and immunohistochemical features, a diagnosis of LGMS was established. The tumor was resected, and no recurrence was observed over 2 years. Although the tongue is the most preferred site for LGMS, it may occur in any region of the oral cavity. 展开更多
关键词 low-grade myofibroblastic sarcoma ORAL PALATE
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Optimal management of biopsy-proven low-grade gastric dysplasia 被引量:13
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作者 Jung-Wook Kim Jae Young Jang 《World Journal of Gastrointestinal Endoscopy》 CAS 2015年第4期396-402,共7页
Gastric adenocarcinoma generally culminates via the inflammation-metaplasia-dysplasia-carcinoma sequence progression. The prevalence of gastric adenomas shows marked geographic variation. Recently, the rate of diagnos... Gastric adenocarcinoma generally culminates via the inflammation-metaplasia-dysplasia-carcinoma sequence progression. The prevalence of gastric adenomas shows marked geographic variation. Recently, the rate of diagnosis of low-grade dysplasia(LGD) has increased due to increased use of upper endoscopy. Many investigators have reported that gastric highgrade dysplasia has high potential for malignancy and should be removed; however, the treatment for gastric LGD remains controversial. Although the risk of LGD progression to invasive carcinoma has been reported to be inconsistent, progression has been observed during follow-up. Additionally, the rate of upgraded diagnosis in biopsy-proven LGD is high. Therefore, endoscopic resection(ER) may be useful in the treatment and diagnosis of LGD, especially if lesions are found to have risk factors for upgraded histology after ER, such as large size, surface erythema or depressed morphology. Fatal complications in endoscopic submucosal dissection(ESD) are extremely low and its therapeutic and diagnostic outcomes are excellent. Therefore, ESD should be applied preferentially instead of endoscopic mucosal resection. 展开更多
关键词 Intraepithelial NEOPLASIA low-grade DYSPLASIA ADENOMA Endoscopic RESECTION Endoscopicsubmucosal dissectio
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Even low-grade inflammation impacts on small intestinal function 被引量:9
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作者 Katri Peuhkuri Heikki Vapaatalo Riitta Korpela 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第9期1057-1062,共6页
Independent of the cause and location,inflammation-even when minimal-has clear effects on gastrointestinal morphology and function.These result in altered digestion,absorption and barrier function.There is evidence of... Independent of the cause and location,inflammation-even when minimal-has clear effects on gastrointestinal morphology and function.These result in altered digestion,absorption and barrier function.There is evidence of reduced villus height and crypt depth,increased permeability,as well as altered sugar and peptide absorption in the small intestine after induction of inflammation in experimental models,which is supported by some clinical data.Identification of inflammatory factors which may promote the process of gastrointestinal dysfunction as well as clinical research to verify experimental observations of inflammatory modulation of gastrointestinal function are required.Moreover,nutritional strategies to support functional restitution are needed. 展开更多
关键词 Small INTESTINE DIGESTION Absorption MOTILITY Permeability low-grade inflammation CYTOKINES
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Kyanite far from equilibrium dissolution rate at 0–22℃ and pH of 3.5–7.5 被引量:1
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作者 Yilun Zhang Donald J.Rimstidt +1 位作者 Yi Huang Chen Zhu 《Acta Geochimica》 EI CAS CSCD 2019年第4期472-480,共9页
Kyanite is an important and slow-dissolving mineral. Earlier work has measured its dissolution rate at high temperature and acidic pH, but experimental measurements at low temperature and near neutral p H were lacking... Kyanite is an important and slow-dissolving mineral. Earlier work has measured its dissolution rate at high temperature and acidic pH, but experimental measurements at low temperature and near neutral p H were lacking. The rate equation by Palandri and Kharaka(A compilation of rate parameters of water–mineral interaction kinetics for application to geochemical modeling. US Geological Survey, Open File Report 2004-1068, 2004) indicates that the rate of kyanite dissolution at room temperature and near neutral pH is on the order of 10^-17 mol m^-2 s^-1, orders of magnitudes slower than most common silicate minerals such as albite and quartz. This study used an externallystirred mixed-flow reactor, which allows high solid:solution ratios, to measure the dissolution rate of kyanite at 0–22 ℃ and pH of 3.5–7.5. The measured dissolution rate of kyanite is 4.6–7.6 9 10-13 mol m^-2 s^-1 at 22℃, and the apparent activation energy is 73.5 kJ mol^-1. This dissolution rate is close to the rate of quartz dissolution and four orders of magnitude faster than the prediction by rate equation of Palandri and Kharaka(2004).Based on our new experimental data, we recommend the following rate equation for modeling the dissolution of kyanite at ambient temperatures.r=ke(-Ea)/R(1/T-1/(298.15))where k = 5.08 9 10-13 mol m^-2 s^-1, and Ea= 73.5 kJ mol^-1. Review of literature data(Carroll in The dissolution behavior of corundum, kaolinite, and andalusite: a surface complex reaction model for the dissolution of aluminosilicate minerals in diagenetic and weathering environs. Dissertation, Northwestern University, 1989) led to a recommended rate equation for andalusite as for T = 25℃ and pH = 2–10:r=k1aH+^n1+k2+k3aH^+^n3where k1= 4.04 9 10^-10 mol m^-2 s^-1, k2= 7.95×10^-10 mol m^-2 s^-1, k3= 1.01×10^-17 mol m^-2 s^-1, n1= 1.2 and n3=-0.6. 展开更多
关键词 KINETICS kyanite REACTION rates Mixed-flow REACTOR
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Structure,Properties and Behavior of Kyanite:Use in Refractory Monolithics 被引量:4
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作者 Musa Karakus Robert Moore 《China's Refractories》 CAS 2003年第3期3-6,共4页
1 Introduction Kyanite is an important naturally occurring in-dustrial mineral and is used in the manufacture of avariety of industrial ceramic products; notable exam-ples include refractories and porcelains. It is a ... 1 Introduction Kyanite is an important naturally occurring in-dustrial mineral and is used in the manufacture of avariety of industrial ceramic products; notable exam-ples include refractories and porcelains. It is a high-pressure polymorph of the aluminosilicates of the ne-sosilicate group, which includes kyanite, sillimanite,and andalusite. These three aluminous or alumina-rich minerals are chemically identical with the compo-sition, Al;SiO;, but have different crystal structuresand physical properties. It is, however, their alumina 展开更多
关键词 of it or on Structure Properties and Behavior of kyanite in
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Hydrometallurgical leaching and kinetic modeling of low-grade manganese ore with banana peel in sulfuric acid 被引量:4
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作者 Sajjad Ali Yaseen Iqbal +4 位作者 Inamullah Khan Ansar Ullah Muhammad Sadiq Muhammad Fahad Khizar Hussain Shah 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2021年第2期193-200,共8页
Manganese was leached from a low-grade manganese ore(LGMO)using banana peel as the reductant in a dilute sulfuric acid medium.The effects of banana peel amount,H2SO4 concentration,reaction temperature,and time on Mn l... Manganese was leached from a low-grade manganese ore(LGMO)using banana peel as the reductant in a dilute sulfuric acid medium.The effects of banana peel amount,H2SO4 concentration,reaction temperature,and time on Mn leaching from the complex LGMO were studied.A leaching efficiency of~98%was achieved at a leaching time of 2 h,banana peel amount of 4 g,leaching temperature of 120°C,manganese ore amount of 5 g,and sulfuric acid concentration of 15vol%.The phase,microstructural,and chemical analyses of LGMO samples before and after the leaching process confirmed the successful leaching of manganese.Furthermore,the leaching process followed the shrinking core model and the leaching rate was controlled by a surface chemical reaction(1−(1−x)^1/3=kt)mechanism with an apparent activation energy of 40.19 kJ·mol^−1. 展开更多
关键词 low-grade manganese ore GLUCOSE LEACHING KINETICS activation energy
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Recovery of zinc from low-grade zinc oxide ores by solvent extraction 被引量:8
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作者 覃文庆 蓝卓越 黎维中 《Journal of Central South University of Technology》 2003年第2期98-102,共5页
The recovery of zinc from low-grade zinc oxide ores with solvent extraction-electrowinning technique was investigated by using D2EHPA as extractant and 260 # kerosene as diluent. The results show that it is possible t... The recovery of zinc from low-grade zinc oxide ores with solvent extraction-electrowinning technique was investigated by using D2EHPA as extractant and 260 # kerosene as diluent. The results show that it is possible to selectively leach zinc from the ores by heap leaching. The zinc concentration of leach solution in the first leaching cycle is 32.57 g/L, and in the sixteenth cycle the zinc concentration is 8.27g/L after solvent extraction. The leaching solution is subjected to solvent extraction, scrubbing and selective stripping for enrichment of zinc and removal of impurities. The pregnant zinc sulfate solution produced from the stripping cycle is suitable for zinc electrowinning. Extra-pure zinc metal was obtained in the electrowinning test under conventional conditions. 展开更多
关键词 ZINC low-grade ZINC oxide ORES HEAP LEACHING SOLVENT extraction
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Suspension calcination and alkali leaching of low-grade high-sulfur bauxite:Desulfurization, mineralogical evolution and desilication 被引量:4
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作者 Hong-fei Wu Jun-qi Li +2 位作者 Chao-yi Chen Fei-long Xia Zhen-shan Xie 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2020年第5期602-610,共9页
To enable the utilization of low-grade and high-sulfur bauxite, the suspension calcination was used to remove the sulfur and the activate silica minerals, and the calcinated bauxite was subjected to a desilication pro... To enable the utilization of low-grade and high-sulfur bauxite, the suspension calcination was used to remove the sulfur and the activate silica minerals, and the calcinated bauxite was subjected to a desilication process in Na OH solution under atmospheric pressure. The desulfurization and desilication properties and mineralogical evolution were studied by X-ray diffraction, thermogravimetry–differential thermal analysis, scanning electron microscopy, and FactSage methods. The results demonstrate that the suspension calcination method is efficient for sulfur removal: 84.21% of S was removed after calcination at 1000°C for 2 min. During the calcination process, diaspore and pyrite were transferred to α-Al2O3, magnetite, and hematite. The phase transformation of pyrite follows the order FeS2 → Fe3O4 → Fe2O3, and the iron oxides and silica were converted into iron silicate. In the alkali-soluble desilication process, the optimum condition was an alkali solution concentration of 110 g/L, a reaction time of 20 min, and a reaction temperature of 95°C. The corresponding desilication ratio and alumina loss ratio were 44.9% and 2.4%, respectively, and the alumina-to-silica mass ratio of the concentrate was 7.9. The Al2O3·2SiO2, SiO2, and Al2O3 formed during the calcination process could react with Na OH solution, and their activity decreased in the order of Al2O3·2 SiO2, SiO2, and Al2O3. 展开更多
关键词 low-grade BAUXITE sulfur SUSPENSION CALCINATION ALKALI-SOLUBLE DESILICATION Bayer process
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Research on new beneficiation process of low-grade magnesite using vertical roller mill 被引量:4
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作者 Chuang Li Chuan-yao Sun +3 位作者 Yu-lian Wang Ya-feng Fu Peng-yun Xu Wan-zhong Yin 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2020年第4期432-442,共11页
We investigated whether the vertical roller mill can be efficiently used in the beneficiation of low-grade magnesite and whether it can improve upon the separation indices achieved by the ball mill.We conducted experi... We investigated whether the vertical roller mill can be efficiently used in the beneficiation of low-grade magnesite and whether it can improve upon the separation indices achieved by the ball mill.We conducted experiments involving the reverse flotation and positive flotation of low-grade magnesite to determine the optimum process parameters,and then performed closed-circuit beneficiation experiments using the vertical roller mill and ball mill.The results show that the optimum process parameters for the vertical roller mill are as follows:a grinding fineness of 81.6wt%of particles less than 0.074 mm,a dodecyl amine(DDA)dosage in magnesite reverse flotation of 100 g·t?1,and dosages of Na2CO3,(NaPO3)6,and NaOL in the positive flotation section of 1000,100,and 1000 g·t?1,respectively.Compared with the ball mill,the use of the vertical roller mill in the beneficiation of low-grade magnesite resulted in a 1.28%increase in the concentrate grade of MgO and a 5.88%increase in the recovery of MgO.The results of our causation mechanism analysis show that a higher specific surface area and greater surface roughness are the main reasons for the better flotation performance of particles ground by the vertical roller mill in the beneficiation of lowgrade magnesite. 展开更多
关键词 low-grade MAGNESITE vertical roller MILL reverse FLOTATION positive FLOTATION NEW BENEFICIATION process
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Investigation on Synthesis of Sintered Mullite from Low-medium Grade Kyanite 被引量:1
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作者 YE Hang SUN Gaoyang +4 位作者 ZHANG Haibo LI Yanjing GAO Changhe LI Yong YE Fangbao 《China's Refractories》 CAS 2019年第1期22-27,共6页
Sintered mullite is prepared by kyanite powder with Al_2O_3 content of 45% and 50%(Yinshan, Nanyang City, China),and the industrial alumina is added to control the chemical composition. The different series of sintere... Sintered mullite is prepared by kyanite powder with Al_2O_3 content of 45% and 50%(Yinshan, Nanyang City, China),and the industrial alumina is added to control the chemical composition. The different series of sintered mullite according to the Al_2O_3 content(45%-70%) are designed. The raw materials are mixed and compacted, and then sintered at different temperatures. Physical properties, phase composition, microstructure and refractoriness under load of the synthesized samples are characterized by physical property test, XRD, SEM and RUL test, in order to confirm the quality of sintering and the relationship between temperature and mullitization reaction. The results show that the sintered mullite from low-medium grade kyanite has well developed mullite crystals and a continuous staggered network structure is formed, which has a significant contribution to increasing the high temperature performance of mullite. 展开更多
关键词 kyanite industrial ALUMINA SINTERING phase composition microstructure
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Very Low-Grade Metamorphism of Clastic Rocks from the Meso-Neoproterozoic and the Paleozoic along the Profile Yueyang-Linxiang in Northeastern Hunan Province and Its Geological Implications 被引量:3
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作者 WANG Hejing YUAN Lei +2 位作者 WANG Ling ZHOU Zhao AN Jiali 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第5期1743-1753,共11页
This study uses illite crystallinity,chlorite crystallinity,illite polytypes,the b0 cell-dimension of K-white mica,clay mineral assemblages and mineral geothermo-geobarometers to investigate the overprint of diagenesi... This study uses illite crystallinity,chlorite crystallinity,illite polytypes,the b0 cell-dimension of K-white mica,clay mineral assemblages and mineral geothermo-geobarometers to investigate the overprint of diagenesis and metamorphism on the Meso-Neoproterozoic and the Lower Paleozoic along the profile Yueyang-Linxiang in northeastern Hunan Province,China.Illite crystallinity Kbler index(KI) of the 〈2μm fractions ranges from 0.225 to 0.485°Δ2θ while chlorite crystallinity Arkai index(AI) ranges from 0.244 to 1.500°Δ2θ.This indicates that the Meso-Neoproterozoic and the Lower Paleozoic along the profile Yueyang-Linxiang were overprinted with diagenesis and anchi- to epimetamorphism.Peak metamorphic temperature is estimated with the IV site chlorite geothermometer roughly at 360℃.The b0 cell dimension values of illites(K-mica) range from 0.9002 to 0.9054 nm and,on average,at 0.9030 nm for the Meso-Neoproterozoic.Based on cumulative frequency curves of illite(K-mica) b0 cell dimension,the peak metamorphic pressure of the MesoNeoproterozoic along the profile Yueyang-Linxiang is derived of an intermediate pressure type.Most illites occur in the 2M1 polytype and some of them in a mixture of 2M1+1M types especially those in the Paleozoic.This result partly agrees with the conclusion of the lower greenschist and greenschist facies of the Lengjiaxi and Banxi Groups.However,it is not agreed with the sedimentary cover from the Sinian to the Lower Paleozoic or from the Banxi Group to the Lower Paleozoic.Crustal thickening due to "collision" between the Yangtze and Cathaysia blocks led to an increase in the thickness of the Meso-Neoproterozoic to ca.14 km and resulted in a temperature increase in those rocks due to burial.The very low grade to low grade metamorphism overprinting the Meso-Neoproterozoic implies that the so called "Chiangnania or Jiangnan orogen" was no relative with the "Grenvillian orogeney;instead,it might be a continuous amalgamation product between the Yangtze and Cathaysia blocks. 展开更多
关键词 DIAGENESIS very low-grade metamorphism illite crystallinity MESO-NEOPROTEROZOIC lowerpalaeozoic
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Acid equilibrium during bioleaching of alkaline low-grade sulfide copper ore 被引量:4
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作者 WEN Jiankang RUAN Renman YAO Guocheng SONG Yongsheng 《Rare Metals》 SCIE EI CAS CSCD 2006年第6期680-686,共7页
This article reports the study on acid equilibrium during bioleaching of alkaline low-grade copper sulfide ore. Adding auxiliary agents 1# (sulfur) and 2# (pyrite) makes bacterial leaching of copper and acid produ... This article reports the study on acid equilibrium during bioleaching of alkaline low-grade copper sulfide ore. Adding auxiliary agents 1# (sulfur) and 2# (pyrite) makes bacterial leaching of copper and acid production carried out simultaneously because the auxiliary agents can be oxidized by bacteria and the oxidation products involve acid. The acid required for dissolving alkaline gangue during bacterial leaching is produced, and acid equilibrium is reached during the ore bio-leaching. The recovery of copper reaches more than 95%. 展开更多
关键词 BIOLEACHING alkaline low-grade copper sulfide ore acid equilibrium process mineralogy auxiliary agent
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