Ahmed Fall - Academia.edu (original) (raw)
Papers by Ahmed Fall
Open Journal of Urology
Background: Hypospadias is a congenital malformation resulting from hypoplasia of the tissues for... more Background: Hypospadias is a congenital malformation resulting from hypoplasia of the tissues forming the ventral face of the penis. It is associated to variable degrees with an ectopic urethral meatus, a penis curvature and a sapper's apron foreskin [1]. The incidence of this malformation varies from country to country. It is estimated at 1/300 male births in France and 0.26/ 1000 in Mexico [1]. In Senegal, the prevalence of this malformation is unknown. Hypospadias surgery has improved significantly in recent years due to a better understanding of the anatomy on the one hand and the improvement of the instruments used during surgery on the other (suture material, surgical magnification, urethral catheter of suitable size). In sub-Saharan Africa and particularly in Senegal, hypospadias surgery remains a challenge due to the unavailability of adequate equipment (lack of microsurgical instruments and surgical loupes). Objective: To evaluate the outcomes of the treatment of hypospadias by the different surgical techniques used in our center as well as their sexual function in adulthood. Patients and Methods: This is a retrospective study, including all patients operated for hypospadias between January 2009 and December 2017 in Urology-Andrology department of Aristide Le Dantec hospital. The studied parameters were: frequency, age, clinical and therapeutic aspects, and their sexual function in adulthood after treatment.
PAMJ Clinical Medicine, 2020
Dakar médical, 2001
Ce travail a pour but d'etudier les particularites de la lithiase vesicale dans nos regions. ... more Ce travail a pour but d'etudier les particularites de la lithiase vesicale dans nos regions. Patients et methode : II s'agit d'une etude retrospective colligeant 94 cas (62 hommes et 32 femmes) de lithiase vesicale sur une periode de 13 ans. Les facteurs lithogenes, les aspects cliniques, paracliniques et therapeutiques ont ete etudies l'analyse morphoconstitutionnelle (morphologie et spectrophotometrie infra-rouge) a ete realisee en collaboration avec le laboratoire Cristal (Centre Hospitalier de St Cloud, France ). L'âge moyen des patients etait de 24,2 ±20,7 ans. Les principaux motifs de consultation etaient la dysurie (n = 36), les douleurs mictionnelles (n = 28), l'hematurie (n = 15). Des facteurs favorisants ont ete notes dans 27% des cas. Dans 10 cas il existait une association fistule vesico-vaginale et lithiase vesicale. Le bilan radiologique etait domine par l'urographie intraveineuse (53,19 % des cas). Le bilan metabolique revelait une hypercal...
International Journal of Clinical Urology, 2020
Objective: To study the epidemiological, diagnostic and therapeutic profile of kidney tumors in a... more Objective: To study the epidemiological, diagnostic and therapeutic profile of kidney tumors in adults over the past five years. Patients and methods: This was a retrospective, descriptive and analytical Study from the 1 st of January 2014 to 31 st of December 2018. All patients aged 18 years or older hospitalized, followed or operated in the service for a kidney tumor were included in the serie. The parameters studied were: epidemiological, clinical and paraclinical aspects, TNM stage (2017), treatment, histological type, evolution and survival. The calculation of survival rate was done with SPSS IBM statistics 24. Results: sixty-seven patients were included. The average annual incidence was 13. The average age of the patients was 49.6±15.6 years. The sex-ratio was 1.2. Hypertension, smoking and obesity were the main risk factors found. The average size of the tumor was 7.7±4.40 cm. The left kidney location was more frequent. Thirteen patients (20%) had a localized tumor in the kidney, twenty patients (31%) had locally advanced cancer and thirty two patients (49%) had metastasized cancer. Forty-seven patients (70%) had surgical treatment, including five patients with an anti-angiogenic adjuvant therapy. Twelve (17.9%) patients had an antiangiogenic therapy only. Clear cell carcinoma was the most common histology type. The overall survival (OS) rate for cancer patients at 2 years was 22% for surgical treatment, 8% for medical treatment. Conclusion: this work reveals that adult kidney cancer affects young adult and is discovered at advanced stages without any significant change in the epidemiological and clinical profile of these cancers during the two decades.
PAMJ Clinical Medicine, 2020
Les rhabdomyosarcomes sont des tumeurs mésenchymateuses rares le plus souvent décrits chez l´enfa... more Les rhabdomyosarcomes sont des tumeurs mésenchymateuses rares le plus souvent décrits chez l´enfant. Nous rapportons un cas diagnostiqué au stade métastatique chez un patient de 77 ans. Le traitement a consisté à une chimiothérapie.
Frontiers in Microbiology, 2020
Soit X une variété lisse sur un corps k et soit l un nombre premier. On construit une suite exact... more Soit X une variété lisse sur un corps k et soit l un nombre premier. On construit une suite exacte 0 → H 0 (X, Ᏼ 3 cont ޚ( l (2))) ⊗ ޚ/ޑ → H 0 (X, Ᏼ 3 ét ޑ( l ޚ/ l (2))) → C tors → 0 où Ᏼ i ét ޑ( l ޚ/ l (2)) et Ᏼ i cont ޚ( l (2)) sont les faisceaux Zariski associés aux cohomologies étale et continue et C est le conoyau de la classe de cycle l-adique définie par Jannsen sur CH 2 (X ޚ⊗) l si l = car k et une variante de celle-ci si l = car k. Si k = ,ރ cela fournit une autre démonstration d'un théorème de Colliot-Thélène-Voisin, qui évite l'utilisation de la conjecture de Bloch-Kato en degré 3. Si k est séparablement clos et l = car k, on obtient, toujours dans l'esprit de Colliot-Thélène et Voisin, une suite exacte 0 → Griff 2 (X, ޚ l) tors → H 3 tr (X, ޚ l (2)) ⊗ ޚ/ޑ → H 0 (X, Ᏼ 3 cont ޚ( l (2))) ⊗ ޚ/ޑ → Griff 2 (X, ޚ l) ⊗ ޚ/ޑ → 0 où H 3 tr (X, ޚ l (2)) est le quotient de la cohomologie l-adique par le premier cran de la filtration par le coniveau et Griff 2 (X, ޚ l) est un groupe de Griffiths l-adique. Si k est la clôture algébrique d'un corps fini et si X est « de type abélien » et vérifie la conjecture de Tate, alors Griff 2 (X, ޚ l) est de torsion et H 0 (X, Ᏼ 3 ét ޑ( l ޚ/ l (2))) est fini si H 3 tr (X, ޑ l (2)) = 0. D'autre part, un théorème de Schoen donne un exemple où H 0 (X, Ᏼ 3 ét ޑ( l ޚ/ l (2))) est fini mais H 3 tr (X, ޑ l (2)) = 0.
Open Journal of Urology, 2020
Background: Over the last 50 years, endourology has revolutionized urological practices worldwide... more Background: Over the last 50 years, endourology has revolutionized urological practices worldwide. This is not so in many urological centers in West Africa. Although, some centers have made progress in the level of urological services that they offer; many of such centers provide rigid urethrocystoscopy services. Rigid urethrocystoscopy is an endoscopic examination that explores the urethra, bladder and prostate in men. Aims: We report the indications, results and pain assessment of rigid urethrocystoscopy in our center. Patients and Methods: We carried out a retrospective, descriptive, monocentric study in our center between January 2016 and June 2018. The study included all patients who had a rigid urethrocystoscopy under local anaesthesia. We studied the following parameters: sex, age, indications for the examination, outcomes and the pain assessment. Results: Five hundred and forty-one patients were included. The sex-ratio was 1.49. The mean age was 49.47 ± 18.48 years (12 years and 91 years). Lower urinary tract symptoms (29%) and hematuria (28%) were the most common indications. The rigid urethrocystoscopy was normal in 26.8% of patients. Bladder tumors (21.2%) were the most frequent lesions. In men, prostate tumors were more common (21%) followed by bladder tumors (17.9%), while in women, bladder tumors (26.3%) were predominant followed by cystopathy lesions (12.4%).The mean Simple Verbal Scale (SVS) score was 1.25 in women and 2.1 in men. Conclusion: Rigid urethrocystoscopy was relatively well tolerated by our patients. Hematuria was the primary indication and the main etiologies were bladder and prostate tumors.
PAMJ Clinical Medicine, 2020
The purpose of our study was to report catheter implantation technique for the treatment of perit... more The purpose of our study was to report catheter implantation technique for the treatment of peritoneal dialysis as well as the immediate complications of this surgical procedure. We conducted a retrospective study in the Department of Urology at the Hospital Center University Aristide Le Dantec. The study focused on the medical records of patients who had undergone catheter implantation for the treatment of peritoneal dialysis over the period January 2010-June 2016. Data from the medica records of 114 patients were collected. The average age of patients was 45.9 years; there was a female predominance (64%). Double-cuff Tenckhoff catheter was implanted in all patients. Surgery was performed in all patients on an outpatient basis under local anesthesia. The implantation was made by an urological surgeon in 34% of cases. Paramedian laparotomy was the only surgical technique used. Radiography of abdomen without preparation was systematically performed in all patients on the 1st postoperative day. Immediate surgical complications were reported in 17 patients (14.9%). The incorrect position of the catheter was the most common complication. The treatment of these complications was based on surgery in 12 patients. Catheter implantation for peritoneal dialysis by open surgery is simple and fast. It seems well adapted to countries with limited technical equipment.
African Journal of Urology, 2015
MOTS CLÉS Adénocarcinome prostatique; Masse hypogastrique; Traitement hormonal Résumé L'adénocarc... more MOTS CLÉS Adénocarcinome prostatique; Masse hypogastrique; Traitement hormonal Résumé L'adénocarcinome est le type histologique le plus fréquent de cancer de la prostate. Les auteurs rapportent un cas d'adénocarcinome avec un aspect clinique inhabituel, caractérisé par une volumineuse masse hypogastrique simulant un globe vésical. La prise en charge du patient par les agonistes de la LH-RH a permis une nette régression du volume de la masse tumorale dés le troisième mois de traitement.
Progrès en urologie : journal de l'Association française d'urologie et de la Société française d'urologie, 2000
The authors report the case of a patient presenting with recurrent urinary tract infection and de... more The authors report the case of a patient presenting with recurrent urinary tract infection and deterioration of the general status. Ultrasonography, plain x-rays and especially cystoscopy demonstrated the presence in the bladder of an intrauterine contraceptive device inserted 4 years previously. Endoscopic removal combined with antibiotics ensured cure of this patient.
Progrès en Urologie, 2007
Acta Medica Scandinavica, 2009
Different methods for the prevention and treatment of vitamin D deficiency were studied in 42 ins... more Different methods for the prevention and treatment of vitamin D deficiency were studied in 42 institutionalized elderly people. One group received ultraviolet radiation (UVR) on a large area of the body surface once a week for three months. The results were compared with those in groups receiving either 450 IU vitamin D2 together with 420 mg calcium daily, 420 mg calcium alone, or no treatment. A significant increase in serum 25-hydroxyvitamin D was obtained with UVR. A similar increase was obtained with oral vitamin D2. A small but significant decrease in serum alkaline phosphatase was observed in subjects receiving vitamin D and calcium or calcium alone. No effects on serum phosphate, urinary cyclic adenosine monophosphate and urinary calcium were seen. Though brief UVR at one-week intervals is an efficient and safe method for prevention of vitamin D deficiency in the elderly, it is in our experience time-consuming for the ward staff and thus less convenient than oral vitamin D supplementation.
Journal of Business Venturing, 1989
Chemical Engineering Science, 2003
The average supersaturation ÿeld is predicted for precipitations in the case of partially premixe... more The average supersaturation ÿeld is predicted for precipitations in the case of partially premixed feed streams by a simple mixing model from a couple of successive experiments with the same inert tracer by Planar Laser Induced Fluorescence and using a single camera. Then, the mathematical derivation is di erent from that one used for the unmixed feed case. The corresponding experiments have been achieved in a 90 • impinging jets premixer and the supersaturation ÿeld was predicted. Due to the non-simultaneity of tracer experiments, a calculation of the averaged nucleation ux is not possible in the premixed feed case. Nevertheless, a comparison between di erent premixers can be done on the basis of the generated supersaturation levels and fouling risks.
Chemical Engineering Research and Design, 2001
T he mixing of two water feedstreams is investigated in a 0.02 m 3 continuous stirred tank, from ... more T he mixing of two water feedstreams is investigated in a 0.02 m 3 continuous stirred tank, from concentration measurements. These measurements are carried out with a laser sheet in a very thin vertical plane through the vessel tangent to the impeller. The proportionality between the grey level obtained by planar laser induced èuorescence and the local concentration has been previously determined. The éelds of instantaneous concentration, temporal variance and mixing index are processed from the grey level images.
Chemical Engineering & Technology, 2003
The PLIF (Planar Laser Induced Fluorescence Technique) method is applied to determine experimenta... more The PLIF (Planar Laser Induced Fluorescence Technique) method is applied to determine experimentally the field of supersaturation in a separate double jet reactive precipitator from the local instantaneous field of concentrations of an inert tracer. The nucleation flux in the mixing region is derived.
Open Journal of Urology
Background: Hypospadias is a congenital malformation resulting from hypoplasia of the tissues for... more Background: Hypospadias is a congenital malformation resulting from hypoplasia of the tissues forming the ventral face of the penis. It is associated to variable degrees with an ectopic urethral meatus, a penis curvature and a sapper's apron foreskin [1]. The incidence of this malformation varies from country to country. It is estimated at 1/300 male births in France and 0.26/ 1000 in Mexico [1]. In Senegal, the prevalence of this malformation is unknown. Hypospadias surgery has improved significantly in recent years due to a better understanding of the anatomy on the one hand and the improvement of the instruments used during surgery on the other (suture material, surgical magnification, urethral catheter of suitable size). In sub-Saharan Africa and particularly in Senegal, hypospadias surgery remains a challenge due to the unavailability of adequate equipment (lack of microsurgical instruments and surgical loupes). Objective: To evaluate the outcomes of the treatment of hypospadias by the different surgical techniques used in our center as well as their sexual function in adulthood. Patients and Methods: This is a retrospective study, including all patients operated for hypospadias between January 2009 and December 2017 in Urology-Andrology department of Aristide Le Dantec hospital. The studied parameters were: frequency, age, clinical and therapeutic aspects, and their sexual function in adulthood after treatment.
PAMJ Clinical Medicine, 2020
Dakar médical, 2001
Ce travail a pour but d'etudier les particularites de la lithiase vesicale dans nos regions. ... more Ce travail a pour but d'etudier les particularites de la lithiase vesicale dans nos regions. Patients et methode : II s'agit d'une etude retrospective colligeant 94 cas (62 hommes et 32 femmes) de lithiase vesicale sur une periode de 13 ans. Les facteurs lithogenes, les aspects cliniques, paracliniques et therapeutiques ont ete etudies l'analyse morphoconstitutionnelle (morphologie et spectrophotometrie infra-rouge) a ete realisee en collaboration avec le laboratoire Cristal (Centre Hospitalier de St Cloud, France ). L'âge moyen des patients etait de 24,2 ±20,7 ans. Les principaux motifs de consultation etaient la dysurie (n = 36), les douleurs mictionnelles (n = 28), l'hematurie (n = 15). Des facteurs favorisants ont ete notes dans 27% des cas. Dans 10 cas il existait une association fistule vesico-vaginale et lithiase vesicale. Le bilan radiologique etait domine par l'urographie intraveineuse (53,19 % des cas). Le bilan metabolique revelait une hypercal...
International Journal of Clinical Urology, 2020
Objective: To study the epidemiological, diagnostic and therapeutic profile of kidney tumors in a... more Objective: To study the epidemiological, diagnostic and therapeutic profile of kidney tumors in adults over the past five years. Patients and methods: This was a retrospective, descriptive and analytical Study from the 1 st of January 2014 to 31 st of December 2018. All patients aged 18 years or older hospitalized, followed or operated in the service for a kidney tumor were included in the serie. The parameters studied were: epidemiological, clinical and paraclinical aspects, TNM stage (2017), treatment, histological type, evolution and survival. The calculation of survival rate was done with SPSS IBM statistics 24. Results: sixty-seven patients were included. The average annual incidence was 13. The average age of the patients was 49.6±15.6 years. The sex-ratio was 1.2. Hypertension, smoking and obesity were the main risk factors found. The average size of the tumor was 7.7±4.40 cm. The left kidney location was more frequent. Thirteen patients (20%) had a localized tumor in the kidney, twenty patients (31%) had locally advanced cancer and thirty two patients (49%) had metastasized cancer. Forty-seven patients (70%) had surgical treatment, including five patients with an anti-angiogenic adjuvant therapy. Twelve (17.9%) patients had an antiangiogenic therapy only. Clear cell carcinoma was the most common histology type. The overall survival (OS) rate for cancer patients at 2 years was 22% for surgical treatment, 8% for medical treatment. Conclusion: this work reveals that adult kidney cancer affects young adult and is discovered at advanced stages without any significant change in the epidemiological and clinical profile of these cancers during the two decades.
PAMJ Clinical Medicine, 2020
Les rhabdomyosarcomes sont des tumeurs mésenchymateuses rares le plus souvent décrits chez l´enfa... more Les rhabdomyosarcomes sont des tumeurs mésenchymateuses rares le plus souvent décrits chez l´enfant. Nous rapportons un cas diagnostiqué au stade métastatique chez un patient de 77 ans. Le traitement a consisté à une chimiothérapie.
Frontiers in Microbiology, 2020
Soit X une variété lisse sur un corps k et soit l un nombre premier. On construit une suite exact... more Soit X une variété lisse sur un corps k et soit l un nombre premier. On construit une suite exacte 0 → H 0 (X, Ᏼ 3 cont ޚ( l (2))) ⊗ ޚ/ޑ → H 0 (X, Ᏼ 3 ét ޑ( l ޚ/ l (2))) → C tors → 0 où Ᏼ i ét ޑ( l ޚ/ l (2)) et Ᏼ i cont ޚ( l (2)) sont les faisceaux Zariski associés aux cohomologies étale et continue et C est le conoyau de la classe de cycle l-adique définie par Jannsen sur CH 2 (X ޚ⊗) l si l = car k et une variante de celle-ci si l = car k. Si k = ,ރ cela fournit une autre démonstration d'un théorème de Colliot-Thélène-Voisin, qui évite l'utilisation de la conjecture de Bloch-Kato en degré 3. Si k est séparablement clos et l = car k, on obtient, toujours dans l'esprit de Colliot-Thélène et Voisin, une suite exacte 0 → Griff 2 (X, ޚ l) tors → H 3 tr (X, ޚ l (2)) ⊗ ޚ/ޑ → H 0 (X, Ᏼ 3 cont ޚ( l (2))) ⊗ ޚ/ޑ → Griff 2 (X, ޚ l) ⊗ ޚ/ޑ → 0 où H 3 tr (X, ޚ l (2)) est le quotient de la cohomologie l-adique par le premier cran de la filtration par le coniveau et Griff 2 (X, ޚ l) est un groupe de Griffiths l-adique. Si k est la clôture algébrique d'un corps fini et si X est « de type abélien » et vérifie la conjecture de Tate, alors Griff 2 (X, ޚ l) est de torsion et H 0 (X, Ᏼ 3 ét ޑ( l ޚ/ l (2))) est fini si H 3 tr (X, ޑ l (2)) = 0. D'autre part, un théorème de Schoen donne un exemple où H 0 (X, Ᏼ 3 ét ޑ( l ޚ/ l (2))) est fini mais H 3 tr (X, ޑ l (2)) = 0.
Open Journal of Urology, 2020
Background: Over the last 50 years, endourology has revolutionized urological practices worldwide... more Background: Over the last 50 years, endourology has revolutionized urological practices worldwide. This is not so in many urological centers in West Africa. Although, some centers have made progress in the level of urological services that they offer; many of such centers provide rigid urethrocystoscopy services. Rigid urethrocystoscopy is an endoscopic examination that explores the urethra, bladder and prostate in men. Aims: We report the indications, results and pain assessment of rigid urethrocystoscopy in our center. Patients and Methods: We carried out a retrospective, descriptive, monocentric study in our center between January 2016 and June 2018. The study included all patients who had a rigid urethrocystoscopy under local anaesthesia. We studied the following parameters: sex, age, indications for the examination, outcomes and the pain assessment. Results: Five hundred and forty-one patients were included. The sex-ratio was 1.49. The mean age was 49.47 ± 18.48 years (12 years and 91 years). Lower urinary tract symptoms (29%) and hematuria (28%) were the most common indications. The rigid urethrocystoscopy was normal in 26.8% of patients. Bladder tumors (21.2%) were the most frequent lesions. In men, prostate tumors were more common (21%) followed by bladder tumors (17.9%), while in women, bladder tumors (26.3%) were predominant followed by cystopathy lesions (12.4%).The mean Simple Verbal Scale (SVS) score was 1.25 in women and 2.1 in men. Conclusion: Rigid urethrocystoscopy was relatively well tolerated by our patients. Hematuria was the primary indication and the main etiologies were bladder and prostate tumors.
PAMJ Clinical Medicine, 2020
The purpose of our study was to report catheter implantation technique for the treatment of perit... more The purpose of our study was to report catheter implantation technique for the treatment of peritoneal dialysis as well as the immediate complications of this surgical procedure. We conducted a retrospective study in the Department of Urology at the Hospital Center University Aristide Le Dantec. The study focused on the medical records of patients who had undergone catheter implantation for the treatment of peritoneal dialysis over the period January 2010-June 2016. Data from the medica records of 114 patients were collected. The average age of patients was 45.9 years; there was a female predominance (64%). Double-cuff Tenckhoff catheter was implanted in all patients. Surgery was performed in all patients on an outpatient basis under local anesthesia. The implantation was made by an urological surgeon in 34% of cases. Paramedian laparotomy was the only surgical technique used. Radiography of abdomen without preparation was systematically performed in all patients on the 1st postoperative day. Immediate surgical complications were reported in 17 patients (14.9%). The incorrect position of the catheter was the most common complication. The treatment of these complications was based on surgery in 12 patients. Catheter implantation for peritoneal dialysis by open surgery is simple and fast. It seems well adapted to countries with limited technical equipment.
African Journal of Urology, 2015
MOTS CLÉS Adénocarcinome prostatique; Masse hypogastrique; Traitement hormonal Résumé L'adénocarc... more MOTS CLÉS Adénocarcinome prostatique; Masse hypogastrique; Traitement hormonal Résumé L'adénocarcinome est le type histologique le plus fréquent de cancer de la prostate. Les auteurs rapportent un cas d'adénocarcinome avec un aspect clinique inhabituel, caractérisé par une volumineuse masse hypogastrique simulant un globe vésical. La prise en charge du patient par les agonistes de la LH-RH a permis une nette régression du volume de la masse tumorale dés le troisième mois de traitement.
Progrès en urologie : journal de l'Association française d'urologie et de la Société française d'urologie, 2000
The authors report the case of a patient presenting with recurrent urinary tract infection and de... more The authors report the case of a patient presenting with recurrent urinary tract infection and deterioration of the general status. Ultrasonography, plain x-rays and especially cystoscopy demonstrated the presence in the bladder of an intrauterine contraceptive device inserted 4 years previously. Endoscopic removal combined with antibiotics ensured cure of this patient.
Progrès en Urologie, 2007
Acta Medica Scandinavica, 2009
Different methods for the prevention and treatment of vitamin D deficiency were studied in 42 ins... more Different methods for the prevention and treatment of vitamin D deficiency were studied in 42 institutionalized elderly people. One group received ultraviolet radiation (UVR) on a large area of the body surface once a week for three months. The results were compared with those in groups receiving either 450 IU vitamin D2 together with 420 mg calcium daily, 420 mg calcium alone, or no treatment. A significant increase in serum 25-hydroxyvitamin D was obtained with UVR. A similar increase was obtained with oral vitamin D2. A small but significant decrease in serum alkaline phosphatase was observed in subjects receiving vitamin D and calcium or calcium alone. No effects on serum phosphate, urinary cyclic adenosine monophosphate and urinary calcium were seen. Though brief UVR at one-week intervals is an efficient and safe method for prevention of vitamin D deficiency in the elderly, it is in our experience time-consuming for the ward staff and thus less convenient than oral vitamin D supplementation.
Journal of Business Venturing, 1989
Chemical Engineering Science, 2003
The average supersaturation ÿeld is predicted for precipitations in the case of partially premixe... more The average supersaturation ÿeld is predicted for precipitations in the case of partially premixed feed streams by a simple mixing model from a couple of successive experiments with the same inert tracer by Planar Laser Induced Fluorescence and using a single camera. Then, the mathematical derivation is di erent from that one used for the unmixed feed case. The corresponding experiments have been achieved in a 90 • impinging jets premixer and the supersaturation ÿeld was predicted. Due to the non-simultaneity of tracer experiments, a calculation of the averaged nucleation ux is not possible in the premixed feed case. Nevertheless, a comparison between di erent premixers can be done on the basis of the generated supersaturation levels and fouling risks.
Chemical Engineering Research and Design, 2001
T he mixing of two water feedstreams is investigated in a 0.02 m 3 continuous stirred tank, from ... more T he mixing of two water feedstreams is investigated in a 0.02 m 3 continuous stirred tank, from concentration measurements. These measurements are carried out with a laser sheet in a very thin vertical plane through the vessel tangent to the impeller. The proportionality between the grey level obtained by planar laser induced èuorescence and the local concentration has been previously determined. The éelds of instantaneous concentration, temporal variance and mixing index are processed from the grey level images.
Chemical Engineering & Technology, 2003
The PLIF (Planar Laser Induced Fluorescence Technique) method is applied to determine experimenta... more The PLIF (Planar Laser Induced Fluorescence Technique) method is applied to determine experimentally the field of supersaturation in a separate double jet reactive precipitator from the local instantaneous field of concentrations of an inert tracer. The nucleation flux in the mixing region is derived.