期刊文献+
共找到3,612篇文章
< 1 2 181 >
每页显示 20 50 100
Comparative study of thulium fiber laser versus holmium:yttrium-aluminum-garnet laser for ureteric stone management with semi-rigid ureteroscopy: A prospective, single-center study
1
作者 Ankit Gupta Arvind P.Ganpule +3 位作者 Ankush Puri Abhishek G.Singh Ravindra B.Sabnis Mahesh R.Desai 《Asian Journal of Urology》 CSCD 2024年第3期460-465,共6页
Objective:To compare the efficacy and safety of thulium fiber laser(TFL)and holmium:yttrium-aluminum-garnet(Ho:YAG)laser for ureteric stone management with semi-rigid ureteroscopy.Methods:In a prospective study from J... Objective:To compare the efficacy and safety of thulium fiber laser(TFL)and holmium:yttrium-aluminum-garnet(Ho:YAG)laser for ureteric stone management with semi-rigid ureteroscopy.Methods:In a prospective study from January 2020 to December 2021,we compared 40 patients in each group who underwent semi-rigid ureteroscopic lithotripsy with TFL and that with Ho:YAG laser.Stone volume,stone density,stone fragmentation rates,total lasing time,total operative time,endoscopic vision,retropulsion and stone free rates were analyzed in both groups and compared.Results:Mean stone volume was comparable in the TFL group and the Ho:YAG laser group(282.45[standard deviation,SD 139.79]mm3 vs.279.49[SD 312.52]mm3;p=0.964).Mean stone density was also comparable in the TFL group and the Ho:YAG laser group(1135.30[SD 317.04]Hounsfield unit vs.1131.75[SD 283.03]Hounsfield unit;p=0.959).The mean stone fragmentation rates calculated as stone volume divided by lasing time were 25.85(SD 10.61)mm3/min and 21.37(SD 14.13)mm3/min in the TFL group and the Ho:YAG laser group,respectively(p=0.113).The mean total lasing time(10.15[SD]4.69 min vs.11.43[SD 4.56]min;p=0.222),mean operative time(25.13[SD 9.51]min vs.25.54[SD 10.32]min;p=0.866),and mean total hospital stay(2.62[SD 0.77]days vs.2.61[SD 0.84]days;p=0.893)were comparable in the TFL group and in the Ho:YAG group.The vision was better and retropulsion was less in the TFL group.The stone-free rate at 1 month postoperatively was slightly better in the TFL group(100%vs.90%;p=0.095). 展开更多
关键词 LASER STONE Urolithiasis THULIUM holmium
下载PDF
Optimal interval for delayed retrieval surgery with reciprocating morcellators after enucleation of giant prostatic hyperplasia in holmium laser enucleation of the prostate
2
作者 Fumiyasu Endo Masaki Shimbo +2 位作者 Kenji Komatsu Kazuhiro Ohwaki Kazunori Hattori 《Asian Journal of Urology》 CSCD 2024年第3期423-428,共6页
Objective:The aim of this research was to evaluate the efficiency of reciprocating morcellation for removing giant benign prostatic hyperplasia during holmium laser enucleation of the prostate,investigate whether perf... Objective:The aim of this research was to evaluate the efficiency of reciprocating morcellation for removing giant benign prostatic hyperplasia during holmium laser enucleation of the prostate,investigate whether performing morcellation as a two-stage procedure improves tissue retrieval efficiency,and seek to determine the optimal interval between the two surgeries.Methods:This study included nine cases of holmium laser enucleation of the prostate with an enucleated prostate weight exceeding 200 g,indicative of substantial prostate enlargement.Morcellation was performed on Day 0(n=4),Day 4(n=1),Day 6(n=1),and Day 7(n=3).The intervals were compared regarding the morcellation efficiency,beach ball presence,and pathology.Results:The mean estimated prostate volume was 383(range 330e528)mL;the median enucleation weight was 252(interquartile range[IQR]222,342)g;and the median enucleation time was 83(IQR 62,100)min.The mean morcellation efficiency was 1.44(SD 0.55)g/min on Day 0 and 13.69(SD 2.46)g/min on day 7.The morcellation efficiency was 4.15 g/min and 10.50 g/min on Day 4 and Day 6,respectively,with significantly higher in the two-stage group compared to one-stage group(11.0 g/min vs.1.5 g/min;p=0.014).Efficiency was strongly correlated with intervals(p<0.001);the incidences of beach balls were 100%(4/4)and 60%(3/5)in the immediate and two-stage surgery groups,respectively.Conclusion:The efficiency of two-stage morcellation with reciprocating morcellators was highly related to the postoperative interval,with the maximum efficiency reached on Day 7. 展开更多
关键词 holmium laser enucleation of the prostate Reciprocating morcellator Giant adenoma Two-stage surgery
下载PDF
Ureteroscopy with Holmium: YAG Laser—A Initial Study in the Urology Department of the Pr Bocar Sidy Sall University Hospital of Kati
3
作者 Amadou Kassogue Idrissa Sissoko +11 位作者 Daouda Sangare Moussa Salifou Diallo Hamed Sylla Mahamadou Traore Boureima Coulibaly Salia Coulibaly Modibo Diakite Modibo Togola Fadima Tall Ilias Guindo Ben Naoum Kamel Mamadou Lamine Diakite 《Open Journal of Urology》 2024年第4期207-216,共10页
Introduction: Ureteroscopy is a minimally invasive endoscopic surgery which provides access to the ureter, pyelon and calyceal cavities via the urethra and the bladder. Laser ureteroscopy uses the laser as an energy s... Introduction: Ureteroscopy is a minimally invasive endoscopic surgery which provides access to the ureter, pyelon and calyceal cavities via the urethra and the bladder. Laser ureteroscopy uses the laser as an energy source to treat the stone and eliminate it naturally. Minimally invasive endoscopic methods are struggling to become popular in sub-Saharan African countries, especially for the upper urinary tract. The objective of our work was to report the results of our first laser ureteroscopy experience in the department. Materials and Methods: This was a prospective and descriptive study running from December 1, 2023 to February 19, 2024. Included in our study was any case of upper urinary tract stone operated by Laser ureteroscopy. The characteristics of the lithiasis were determined by CT scan. Sterilization of urine was verified by carrying out a cytobacteriological examination of urine. Ureteral lithiasis was approached by semi-rigid ureteroscopy. Renal lithiasis was immediately addressed by flexible ureteroscopy. Ureteroscopy was coupled with a Holmium YAG laser. A double J ureteral catheter was placed after the operation. A 230 µm laser fiber was used in each case with a generator with a power of 35 watts (Storz Calculase III type). An access sheath was used in all cases of flexible ureteroscopy. The parameters studied were: sociodemographic characteristics, lithiasis (site, size, number, density, topography), type of anesthesia, duration of laser use, duration of intervention, postoperative outcomes. Data entry and analysis were carried out using the software (Word 2016 and SPSS). Result: We collected 30 cases of laser ureteroscopy. The average age was 37 years with extremes of 9 and 79 years. The male gender was more represented. The most common age group was 24-39 years old. Renal colic was the most frequent reason for admission, 12 patients (40%). On physical examination, lumbar tenderness was present in 47% (14 patients). ECBU was positive in 4 patients (13%). CT scan was performed in all our patients before the intervention. The average stone size was 12 mm and the largest was 23 mm. The majority of stones, i.e. 59% (18 patients), had a density greater than 1000 HU. The stone was unique in 19 patients (63%). The location of the stone was pyelic in 8 patients or 27%. An impact on the upper urinary tract was found in 16 of our patients or 53%. General anesthesia was used in 25 patients (83%). A digital flexible ureteroscopy was used in 24 patients and a semi-rigid ureteroscopy (URS) in 6 patients. Full-course fragmentation was the most used therapeutic method, 9 patients or 32%. The average duration of interventions was 61 minutes. Drainage by double J catheter at the end of the procedure was performed in all our patients. The length of hospitalization was 24 hours. Only one case of failure in the USSR was recorded, and one case of failure was in the semi-rigid URS. Conclusion: Laser ureteroscopy is an effective minimally invasive surgery in the management of lithiasis of the upper urinary tract. It significantly reduces the length of hospitalization. Mastery of this technique and the acquisition of the equipment necessary for its implementation is an undeniable asset in the management of renal and ureteral lithiasis. 展开更多
关键词 URETEROSCOPY SEMI-RIGID Flexible holmium YAG Laser
下载PDF
A method for reducing thermal injury during the ureteroscopic holmium laser lithotripsy 被引量:1
4
作者 Xiaoliang Zhu Feiping Li +3 位作者 Xixi Hu Haiping Li Songjiang Wu Haihong Jiang 《Asian Journal of Urology》 CSCD 2023年第1期89-95,共7页
Objective:Many studies have demonstrated the heat effect from the holmium laser lithotripsy can cause persistent thermal injury to the ureter.The purpose of this study was to elucidate the use of a modified ureteral c... Objective:Many studies have demonstrated the heat effect from the holmium laser lithotripsy can cause persistent thermal injury to the ureter.The purpose of this study was to elucidate the use of a modified ureteral catheter with appropriate firing and irrigation to reduce the thermal injury to the“ureter”during the ureteroscopic holmium laser lithotripsy in vitro.Methods:An in vitro lithotripsy was performed using a modified catheter(5 Fr)as the entrance for the irrigation and the holmium laser fiber while using the remaining space in the ureteroscopic channel as an outlet.Different laser power settings(10 W,20 W,and 30 W)with various firing times(3 s,5 s,and 10 s)and rates of irrigation(15 mL/min,20 mL/min,and 30 mL/min)were applied in the experiment.Temperature changes in the“ureter”were recorded with a thermometer during and after the lithotripsy.Results:During the lithotripsy,the local highest mean temperature was 60.3℃ and the lowest mean temperature was 26.7℃.When the power was set to 10 w,the temperature was maintained below 43℃ regardless of laser firing time or irrigation flow.Regardless of the power or firing time selected,the temperature was below 43℃ at the rate of 30 mL/min.There was a significant difference in temperature decrease when continuous 3 s drainage after continuous firing(3 s,5 s,or 10 s)compared to with not drainage(p<0.05)except for two conditions of 0.5 J×20 Hz,30 mL/min,firing 5 s,and 1.0 J×10 Hz,30 mL/min,firing 5 s.Conclusion:Our modified catheter with timely drainage reducing hot irrigation may significantly reduce the local thermal injury effect,especially along with the special interrupted-time firing setting during the simulated holmium laser procedure. 展开更多
关键词 Modified catheter holmium laser LITHOTRIPSY Thermal injury
下载PDF
Primary prostate Burkitt's lymphoma resected with holmium laser enucleation of the prostate:A rare case report 被引量:1
5
作者 Yu-Fan Wu Xiang Li +4 位作者 Jun Ma Dan-Yu Ma Xue-Ming Zeng Qi-Wei Yu Wei-Guo Chen 《World Journal of Clinical Cases》 SCIE 2023年第18期4406-4411,共6页
BACKGROUND Primary prostate Burkitt's lymphoma is a rare and aggressive condition with a poor prognosis.Its clinical presentation can be challenging to differentiate from benign prostatic hyperplasia.Given the rar... BACKGROUND Primary prostate Burkitt's lymphoma is a rare and aggressive condition with a poor prognosis.Its clinical presentation can be challenging to differentiate from benign prostatic hyperplasia.Given the rarity of primary prostate Burkitt's lymphoma,its diagnosis and treatment remain unclear.CASE SUMMARY This report presents a case of a 57-year-old male with primary prostate Burkitt's lymphoma,initially misdiagnosed as prostatic hyperplasia.This case's operative process,intraoperative findings and postoperative management are discussed in detail.CONCLUSION Primary prostate lymphoma is difficult to distinguish from other prostate diseases.Holmium laser enucleation of the prostate(HoLEP),a minimally invasive procedure,is crucial in diagnosing and treating this rare disease.Clinicians should remain vigilant and thoroughly combine physical examination,imaging and test results when encountering patients of younger age with small prostate size but a rapid progression of lower urinary tract symptoms.HoLEP is an essential diagnostic and therapeutic tool in managing primary prostate Burkitt's lymphoma. 展开更多
关键词 Primary prostate Burkitt's lymphoma holmium Laser enucleation of the prostate Prostate hyperplasia Case report
下载PDF
Analysis of the effect of holmium laser flexible ureteroscopic intrapelvic drainage in the treatment of parapelvic renal cysts
6
作者 Yuanshen Mao Wenfeng Li +5 位作者 Jun Da Mingxi Xu Yiwei Wang Yufei Gu Weixin Pan Zhong Wang 《Asian Journal of Urology》 CSCD 2023年第2期172-176,共5页
Objective:To explore the efficacy,safety,and feasibility of holmium laser flexible ureteroscopic intrapelvic drainage in the treatment of parapelvic renal cysts.Methods:From September 2012 to February 2019,a total of ... Objective:To explore the efficacy,safety,and feasibility of holmium laser flexible ureteroscopic intrapelvic drainage in the treatment of parapelvic renal cysts.Methods:From September 2012 to February 2019,a total of 18 patients,aged from 28 to 62(meanstandard deviation[SD]:46.50±9.14)years,were diagnosed with parapelvic renal cysts and treated by holmium laser flexible ureteroscopic intrapelvic drainage.There were 10 males and eight females.All of the parapelvic renal cysts were unilateral,and two cases were complicated with pyelolithiasis.The diameters of the cysts ranged from 4.1 cm to 8.2 cm.Results:All the patients completed the operation successfully in one stage without conversion to open surgery;in two cases,it was difficult to find the cysts during the operation,and the localization was completed by B-ultrasound and percutaneous injection of methylene blue.The mean operative time was 33.89(SD:9.68;range:22-54)min,and the mean hospitalization time was 2.67(SD:0.91;range:2-5)days.Three months and 6 months of follow-up were performed after surgery.The cysts disappeared in 13(72%)cases,and the diameter of the cysts in five(28%)cases decreased by more than 50%.Conclusion:Holmium laser flexible ureteroscopic intrapelvic drainage in the treatment of parapelvic renal cysts is simple,safe,and effective,and can be used as the first choice for the treatment of parapelvic renal cysts. 展开更多
关键词 Flexible ureteroscopy holmium laser Parapelvic renal cyst B-ULTRASOUND Intrapelvic drainage
下载PDF
Preparation of Terbium Sesquisulfide and Holmium Sesquisulfide by Sulfurization of Their Oxide Powders Using CS_2 Gas 被引量:5
7
作者 YuanHaibin MichihiroOhta +2 位作者 ShinjiHirai ToshiyukiNishimura KazuyoshiShimakage 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第6期759-762,共4页
The formation behaviors of terbium sesquisulfide(Tb_2S_3)and holmium sesquisulfide(Ho_2S_3)synthesized via the sulfurization of their oxide powders using CS_2 gas in the range of temperature 673 to 1323 K were investi... The formation behaviors of terbium sesquisulfide(Tb_2S_3)and holmium sesquisulfide(Ho_2S_3)synthesized via the sulfurization of their oxide powders using CS_2 gas in the range of temperature 673 to 1323 K were investigated. In the sulfurization of Tb_4O_7 powder, Tb_2O_3 and Tb_2O_2S were formed in the initial stage of reaction, and α-Tb_2S_3 was finally formed at higher temperature. For long sulfurization time of 8 h, single-phase α-Tb_2S_3 could be synthesized at 1323 K. In the sulfurization of Ho_2O_3 powder using CS_2 gas, only Ho_2O_2S was formed as an intermediate product. At a sulfurization temperature above 873 K, Ho_2O_2S was formed in the initial stage of reaction, and single-phase δ-Ho_2S_3 was formed at 1323 K for 8 h instead of Ho_2O_2S. Furthermore, the influence of the addition of carbon black to the sulfurization of Ho_2O_3 powder using CS_2 gas was investigated, and the result implied that the reactions were accelerated slightly by the addition of carbon black. 展开更多
关键词 terbium sesquisulfide holmium sesquisulfide carbon disulfide SULFURIZATION impurity content
下载PDF
Preparation, Structure, Photoluminescence and Energy Transfer Mechanism of a Novel Holmium Complex 被引量:5
8
作者 KUANG Han-Mao ZHANG Zhuan-Xia +2 位作者 LIN Long-Zhen CHEN Hua-Long CHEN Wen-Tong 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第3期337-344,共8页
A novel holmium complex [Ho(HIA)_2(H_2O)_4(NO_3)](NO_3)_2(1, HIA = isonicotinic acid) has been synthesized through hydrothermal reactions and characterized by single-crystal X-ray diffraction. Complex 1 crystallizes i... A novel holmium complex [Ho(HIA)_2(H_2O)_4(NO_3)](NO_3)_2(1, HIA = isonicotinic acid) has been synthesized through hydrothermal reactions and characterized by single-crystal X-ray diffraction. Complex 1 crystallizes in the C2/c space group of monoclinic system: a = 14.4797(7), b = 12.4768(2), c = 13.3471(5) ?, β = 118.690(4)°, V = 2115.26(13) ?~3, C_(12)H_(16)HoN_5O_(17), Mr = 667.23, Z = 4, Dc = 2.095 g/cm^3, μ(Mo Kα) = 3.838 mm^(–1) and F(000) = 1304. The crystal structure of 1 is characterized by an isolated structure. Solid-state photoluminescence experiment uncovers that it shows yellow light emission. The emission bands are originated from the characteristic emission of the 4 f electrons intrashell transition of the ~5S_2 → ~5I_8 and ~5F_5 → ~5I_8 of the Ho^(3+) ions. Energy transfer mechanism is explained by the energy level diagram of the Ho3+ ion and the isonicotinic acid ligand. It has remarkable CIE chromaticity coordinates of(0.4929, 0.4632), so it may be a promising color converter for lighting and displays. 展开更多
关键词 crystal CIE energy TRANSFER MECHANISM holmium PHOTOLUMINESCENCE
下载PDF
Coagulation of a giant hemangioma in glans penis with holmium laser 被引量:4
9
作者 Emin Aydur Bulent Erol +3 位作者 Lutfi Tahmaz Hasan Cem Irkilata Cenker Eken Ahmet Fuat Peker 《Asian Journal of Andrology》 SCIE CAS CSCD 2008年第5期819-821,共3页
A 21-year-old man presented with an enlarged giant hemangioma on glans penis which also causes an erectile dysfunction (ED) that partially responded to the intracavernous injection stimulation test. Although the fin... A 21-year-old man presented with an enlarged giant hemangioma on glans penis which also causes an erectile dysfunction (ED) that partially responded to the intracavernous injection stimulation test. Although the findings in magnetic resonance imaging (MRI) indicated a glandular hemangioma, penile colored Doppler ultrasound revealed an invaded cavernausal hemangioma to the glans. Surgical excision was avoided according to the broad extension of the gland lesion. Holmium laser coagulation was applied to the lesion due to the cosmetically concerns. However, the cosmetic results after holmium laser application was not impressive as expected without an improvement in intracavernous injection stimulation test. In conclusion, holmium laser application should not be used to the hemangiomas of glans penis related to the corpus cavernosum, but further studies are needed to reveal the effects of holmium laser application in small hemangiomas restricted to the glans penis. 展开更多
关键词 lasers penis erectile dysfunction HEMANGIOMA holmium laser
下载PDF
Crystal structure and infrared spectrum of thallium holmium polyphosphate, TlHo(PO_3)_4 被引量:2
10
作者 Karima Horchani-Naifer Jaouher Amami Mokhtar Férid 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第6期765-769,共5页
Crystals of thallium-holmium polyphosphate T1Ho(PO3)4 were grown by flux method technique and characterized by single crystal X-ray diffraction. Structure of T1Ho(PO3)4 was solved for the first time, and it crysta... Crystals of thallium-holmium polyphosphate T1Ho(PO3)4 were grown by flux method technique and characterized by single crystal X-ray diffraction. Structure of T1Ho(PO3)4 was solved for the first time, and it crystallized in the monoclinic P21/n space group with the following unit-cell dimensions: a=1.02225(3) nm, b=0.88536(2) nm, c=1.09541(4) nm, β=105.888(1)°, V=0.95354(5) nm^3 and Z=4. The crystal structure was solved from 2174 independent reflections with final R1(F^2)=0.0442 and Rw(F^2)=0.0861 refined with 164 parameters. The atomic arrangement could be described as a long chain polyphosphate organization. Holmium atoms had eightfold coordination. The structure of T1Ho(PO3)4 consisted of HoO8 polyhedra sharing oxygen atoms with phosphoric group PO4. Infrared spectrum was investigated at room temperature in the frequencies range, 350--4000 cm^-1, showing some characteristic vibration bands of infinite chain structure of PO4 tetrahedra linked by bridging oxygen. 展开更多
关键词 POLYPHOSPHATE holmium crystal structure infrared spectroscopy rare earths
下载PDF
Ureteroscopic Holmium:YAG Laser Lithotripsy for Managing Ureteral Calculi (A Report of 168 Cases) 被引量:3
11
作者 庞自力 肖传国 曾甫清 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2004年第3期305-306,共2页
Summary: The effectiveness and safety of ureteroscopic holmium:YAG laser lithotripsy for managing ureteral calculi was evaluated. Ureteroscopic holmium:YAG laser lithotripsy was performed in 168 ureteral calculi (uppe... Summary: The effectiveness and safety of ureteroscopic holmium:YAG laser lithotripsy for managing ureteral calculi was evaluated. Ureteroscopic holmium:YAG laser lithotripsy was performed in 168 ureteral calculi (upper 27 cases, middle 33 cases and lower 108 cases). The results showed that the stone-free rate was 92.6 % in the upper ureteral calculi, 93.9 % in the middle ureteral calculi and 94.4 % in the lower ureteral calculi, respectively. The complication rate was 4.8 % (8 cases). It was suggested that ureteroscopic holmium:YAG laser lithotripsy is a highly effective and safe treatment modality for managing ureteral calculi. 展开更多
关键词 holmium:YAG laser lithotripsy URETEROSCOPY ureteral calculi
下载PDF
Treatment of Special Renal Colic with Ureteroscope and Holmium YAG Laser 被引量:3
12
作者 沈明顺 刘军 《Journal of Nanjing Medical University》 2002年第3期135-137,共3页
Objective To investigate the method of emergent relief of special renal colic and treatment of ureter diseases causing renal colic. Methods By analyzing 63 cases of special renal colic treated with ureteroscope and ... Objective To investigate the method of emergent relief of special renal colic and treatment of ureter diseases causing renal colic. Methods By analyzing 63 cases of special renal colic treated with ureteroscope and Holmium YAG laser. Results 61 cases of renal colic were relieved in a short period of time and the original ureter diseases causing renal colic were cured. Conclusion Special renal colic could be treated with ureteroscope and Holmium YAG laser in a quick and effective manner. 展开更多
关键词 renal colic ureterscope holmium YAG laser
下载PDF
Thermochemical Study of Coordination of Holmium Chloride Hydrate with Diethylammonium Diethyldithiocarbamate 被引量:1
13
作者 ZHAO Feng-qi CHEN San-ping +3 位作者 JIAO Bao-juan REN Yi-xia GAO Sheng-li SHI Qi-zhen 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第6期766-770,共5页
The complex of holmium chloride hydrate with diethylammonium diethyldithiocarbamate(D-DDC) was synthesized via mixing their solutions in absolute alcohol under a dry N 2 atmosphere. The elemental and chemical analyse... The complex of holmium chloride hydrate with diethylammonium diethyldithiocarbamate(D-DDC) was synthesized via mixing their solutions in absolute alcohol under a dry N 2 atmosphere. The elemental and chemical analyses show that the complex has the general formula Et 2NH 2[Ho(S 2CNEt 2) 4]. It was also characterized by IR spectroscopy. The enthalpies of the dissolution of holmium chloride hydrate and D-DDC in absolute alcohol at 298.15 K, and the enthalpy changes of liquid-phase reactions of the formation of Et 2NH 2[Ho(S 2CNEt 2) 4] at different temperatures were determined by microcalorimetry. On the basis of experimental and calculated results, three thermodynamic parameters(the activation enthalpy, the activation entropy and the activation free energy), the rate constant and three kinetic parameters(the apparent activation energy, the pre-exponential constant and the reaction order) of the liquid-phase reaction of the complex formation were obtained. The enthalpy change of the solid-phase complex formation reaction at 298.15 K was calculated by means of a thermochemical cycle. 展开更多
关键词 holmium chloride hydrate Diethylammonium diethyldithiocarbamate(D-DDC) Microcalori-metric method THERMOCHEMISTRY
下载PDF
Growth and Characterization of Holmium Oxalate Heptahydrate Crystals 被引量:1
14
作者 Basharat Want Feroz Dar 《Journal of Crystallization Process and Technology》 2012年第4期137-141,共5页
Single crystals of holmium oxalate heptahydrate are grown by gel diffusion method using organic agar gel as a medium of growth. The crystals grow in the agar gel with hexagonal morphology having well defined habit fac... Single crystals of holmium oxalate heptahydrate are grown by gel diffusion method using organic agar gel as a medium of growth. The crystals grow in the agar gel with hexagonal morphology having well defined habit faces Powder X-ray diffraction results show that the crystals belong to monoclinic system bearing the space group P21/c with cell parameters;a = 12.197? , b = 11.714 , c = 6.479 , α = 90°, β = 120.12°, γ = 90°, V = 799.6? 3. Fourier transform Infrared spectrum of the crystals shows the presence of water and other associated functional groups. Thermogravimetric analysis support the presence of 7 H2O molecules associated with holmium oxalate crystal lattice. The thermal decomposition in the nitrogen atmosphere leads to the formation of holmium oxide as the final product. 展开更多
关键词 holmium OXALATE Heptahydrate Single Rystals X-RAY DIFFRACTION THERMOGRAVIMETRIC Analysis
下载PDF
Electrochemical formation of holmium-cobalt alloys 被引量:1
15
作者 SUYuzhi YANGQiqin LIUGuankun 《Rare Metals》 SCIE EI CAS CSCD 2003年第1期19-24,共6页
The electrochemical formation processes of holmium-cobalt alloys on cobaltcathode in molten HoCl_3-KCl were investigated by cyclic voltammetry and open current potential-timecurve alter potentiostatic electrolysis. Th... The electrochemical formation processes of holmium-cobalt alloys on cobaltcathode in molten HoCl_3-KCl were investigated by cyclic voltammetry and open current potential-timecurve alter potentiostatic electrolysis. The structure of Ho-Co alloys' films deposited on cobaltelectrode by potentiostatic electrolysis was characterized by X-ray diffraction. The standard Gibbsfree energies of formation for the intermetallic compounds of Ho and Co were determined. Thediffusion coefficient and diffusion activation energy of Ho atom in the alloy phase were calculatedto be 10^(-10) -10^(-11) cm^2/s and 96.0 kJ/mol, respectively, from the current-time curve atpotential step. 展开更多
关键词 rare earths holmium-cobalt alloy electrochemical formation moltenchloride Gibbs free energy of formation diffusion coefficient
下载PDF
Comparison of the curative effect and serum indexes of ultrasonic pneumatic and holmium laser technology for percutaneous nephrolithotomy treatment of complex renal calculus 被引量:1
16
作者 Cheng-Jun Qiu Jin-Song Ao +3 位作者 Li Cheng Bo Wang Yu Zhou Chang-Zhong Wang 《Journal of Hainan Medical University》 2017年第6期68-71,共4页
Objective:To study the differences in the curative effect and serum indexes of ultrasonic pneumatic and holmium laser technology for percutaneous nephrolithotomy treatment of complex renal calculus.Methods: A total of... Objective:To study the differences in the curative effect and serum indexes of ultrasonic pneumatic and holmium laser technology for percutaneous nephrolithotomy treatment of complex renal calculus.Methods: A total of 78 patients with complex renal calculus who accepted surgical treatment in our hospital between May 2011 and January 2016 were collected, the operation methods and test results were reviewed, and then they were divided into the observation group (n=34) who accepted ultrasonic pneumatic treatment and the control group (n=44) who accepted holmium laser treatment.Ⅰstage stone clearance rate of two groups of patients were recorded;serum was collected, sarcosine oxidase method was used to detect serum renal function indexes, and ELISA method was used to detect the levels of inflammatory factors and stress hormones.Results: The mean lithotomy time of observation group was shorter than that of control group;differences inⅠstage stone clearance rate were not statistically significant between two groups of patients. 3 d after operation, serum renal function indexes Scr, BUN and CysC levels of observation group were lower than those of control group;serum inflammatory factors PCT, IL-1β, IL-22 and IL-13 levels of observation group were lower than those of control group while IL-4 level was higher than that of control group;serum stress hormones AngⅠ, AngⅡ, Adr and NE levels of observation group were lower than those of control group.Conclusion:Both ultrasonic pneumatic and holmium laser technology can effectively remove complex renal calculus and ultrasonic pneumatic technology has the advantages of quicker operation and less injury. 展开更多
关键词 COMPLEX RENAL CALCULUS ULTRASONIC PNEUMATIC holmium laser Stress response Inflammatory factors
下载PDF
Determination of Compositions and Stability Constants of Holmium and Yttrium Complexes with Tribromoarsenazo by Linear Regression Method
17
作者 魏永巨 丁儒乾 《Journal of Rare Earths》 SCIE EI CAS CSCD 1991年第1期5-9,共5页
According to the appearing of isosbestic point in the absorption spectra of Ho/Y-Tribromoarsenazo (TBA)systems,the complexation reaction is considered to be M+nL=ML_n.A method has been proposed based on it for calcula... According to the appearing of isosbestic point in the absorption spectra of Ho/Y-Tribromoarsenazo (TBA)systems,the complexation reaction is considered to be M+nL=ML_n.A method has been proposed based on it for calculating the mole fraction of free complexing agent in the solutions from spectral data.and two linear regression formula have been introduced to determine the composition,the molar absorptivity,the conditional stability constant of the complex and the concentration of the complexing agent. This method has been used in Ho-TBA and Y-TBA systems.Ho^(3+)and Y^(3+)react with TBA and form 1: 2 complexes in HCl-NaAc buffer solution at pH 3.80.Their molar absorptivities determined are 1.03×10~8 and 1.10×10~8 cm^2·mol^(-1),and the conditional stability constants(logβ_2)are 11.37 and 11.15 respectively.After considering the pH effect in TBA complexing,their stability constants(log β_2^(ahs))are 43.23 and 43.01. respectively.The new method is adaptable to such systems where the accurate concentration of the complexing agent can not be known conveniently. 展开更多
关键词 holmium YTTRIUM TRIBROMOARSENAZO Absorption spectra Stablilty constant Linear regression method
下载PDF
Study on Quenching Effect of Holmium (Ⅲ) Ion in Chemiluminescence System of Luminol H_2O_2-Cr(Ⅲ) by Flow Injection Technique
18
作者 朱智甲 《Rare Metals》 SCIE EI CAS CSCD 2000年第1期39-41,共3页
A new chemiluminescence (CL) analytical method for determination of rare earth Ho(Ⅲ) ion is reported. It is based on the quenching effect of Ho(Ⅲ) ion on CL intensity of Luminol H 2O 2 Cr(Ⅲ) system. The detecti... A new chemiluminescence (CL) analytical method for determination of rare earth Ho(Ⅲ) ion is reported. It is based on the quenching effect of Ho(Ⅲ) ion on CL intensity of Luminol H 2O 2 Cr(Ⅲ) system. The detection limit is 3×10 -8 mol/L, the linear range is from 1×10 -7 to 1×10 -4 mol/L; the relative standard deviation is less than 3% (for 2×10 -7 mol/L Ho, n=11). The method was applied to determination of Ho(Ⅲ) in pure samples with satisfactory results. 展开更多
关键词 holmium Flow injection Chemiluminescence analysis LUMINOL
下载PDF
Holmium-doped Porous Silicon Prepared by a New Electrochemical Approach and Its Photoluminescence
19
作者 龚孟濂 曾春莲 +3 位作者 黄伟国 谢国伟 郑婉华 廉德亮 《Journal of Rare Earths》 SCIE EI CAS CSCD 1998年第3期13-18,共6页
Porous silicon(PS) was found to emit visible luminescence at room temperature. This phenomenon implies a potential application of silicon in optoelectronics. The luminescence of PS can be improved by doping with rare ... Porous silicon(PS) was found to emit visible luminescence at room temperature. This phenomenon implies a potential application of silicon in optoelectronics. The luminescence of PS can be improved by doping with rare earth elements. A new electrochemical doping approach, constant potential electrolysis, and a new electrolyte system for doping of porous silicon with holmium were reported. By this approach and system, the doping products were well controlled, and Ho doped PS(HDPS) was found to emit much intenser visible photoluminescence with blue shift in wavelength and higher luminescence stability at room temperature than that for corresponding PS wafer. The effects of various kinds of holmium compounds, solvents, applied voltage, concentration of holmium nitrate and doping time on photoluminescence of HDPS were investigated, and the optimum doping conditions were fixed. The luminescence mechanisms for PS and HDPS were discussed. 展开更多
关键词 Rare earths holmium doped porous silicon Constant Potential electrolysis PHOTOLUMINESCENCE
下载PDF
Synthesis and Crystal Structure of a Two-dimensional Polymeric Holmium Complex〔Ho(H_(2)saln)_(1.5)(NO_(3))_(3)〕
20
《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1999年第2期66-69,共4页
The title polymeric complex Ho(H 2saln) 1.5 (NO 3) 3 (H 2saln= N,N’ bissalicyclidene ethylenediamine) C 24 H 24 N 6O 12 Ho was prepared and its crystal was characterized by X ray diffrac... The title polymeric complex Ho(H 2saln) 1.5 (NO 3) 3 (H 2saln= N,N’ bissalicyclidene ethylenediamine) C 24 H 24 N 6O 12 Ho was prepared and its crystal was characterized by X ray diffraction. The ligand is dischiff base from salicylaldehyde and ethylenediamine. The complex crystallizes in trigonal system, space group P3c1 (No. 165), M r=753.42, a=15.818(2), c=16.978(3) , V=3681(2) 3, D x =1.360 g/cm 3, Z=4, μ =2.2286 mm -1 , F(000)=1492, R=0.049, R w =0.061. In the complex the coordination number of Ho(Ⅲ) is 9 with the geometry of a tricapped trigonal prism. All of the coordination atoms are oxygen atoms. The Ho(Ⅲ) ions are bridged by the dischiff base to form an infinite two dimensional polymeric network, parellel to the (001) plane. 展开更多
关键词 holmium COMPLEX dischiff base N N’ disalicyclideneethylenediamine crystal structure
下载PDF
上一页 1 2 181 下一页 到第
使用帮助 返回顶部