Calcium carbonate fouling on double-pipe heat exchanger with different heat exchanging surfaces

An experimental setup of double pipe heat exchanger fouling test rig was built to investigate the mineral scale deposition on different heat exchanger pipe surfaces. Progressive fouling deposition on different material surfaces under the similar solution conditions were observed and analyzed. Measurable data on the progressive build-up of scale deposits, deposition rate, as well as the composition and crystal morphology of the deposits were studied after each experimental run by analyzing the deposited scale on the test pipes. In this research the artificial calcium carbonate deposit on different material surfaces is considered as it is one of the major constituents of the most scales found in heat exchanging equipment. Fouling on different smooth test pipes were investigated in the centrally located larger concentric pipe heat exchanger. Uniform flow condition near the pipe surface was maintained by constant flow rate throughout the system. The calcium carbonate deposition rates on five different metal surfaces (Stainless steel 316, brass, copper, aluminium and carbon steel) were investigated. The results illustrated an upward trend for fouling rate with time on the tested specimens. The deposition on the surfaces showed a linear growth with the enhancement of thermal conductivity of the metals. However, deposition on carbon steel metal surfaces did not follow the typical linear trend of thermal conductivity over deposition as its surface was altered by corrosion effects. In addition, temperature, velocity, and concentration effects on fouling deposition were investigated on the SS316 metal surface. It is noted that the fouling deposition increases with the increase of temperature and concentration due to enhanced deposition potential whereas reduces due to the increase of velocity which enhances shear stress. © 2017 Elsevier B.V

Two New Species of Symbiotic Ciliates From the Respiratory Tract of Cetaceans With Establishment of the New Genus Planilamina n. Gen. (Dysteriida, Kyaroikeidae)

Examination of mucus discharged from the blowhole of Atlantic bottlenose dolphin (Tursiops truncatus) at Marine Life Oceanarium, Gulfport, Mississippi, and false killer whale (Pseudorca crassidens) and Atlantic bottlenose dolphin at SeaWorld Orlando, Orlando, Florida, using live observations and protargol impregnation revealed mixed infections of Kyaroikeus cetarius and two new species. Planilamina n. gen. is characterized by a C-shaped argentophilic band located along the laterally flattened margin of cell and extending from the cell apex to subposterior cone-shaped podite; a deep oral cavity containing one short preoral kinety, two circumoral kineties, seven to 13 infundibular kineties, and a cytostome; a broadly funnel-shaped cytopharynx reinforced by argentophilic fibers but without nematodesmata; closely packed postoral kinetofragments set in a pocket located anterior left of the podite; and somatic kineties as a right field closely situated at the right surface and a left field bordering the anterior left margin of the oral cavity. The type species for the genus, Planilamina ovata n. sp., is distinguished from its sister species Planilamina magna n. sp. by the following characteristics: body size (28-65 x 20-43 mu m vs. 57-90 x 40-63 mu m), number of right field kineties (38-55 vs. 79-99), and position of the anterior end of the leftmost kinety in the right somatic field (anterior one-third vs. mid-body). The morphogenesis of Planilamina ovata is similar to that of K. cetarius. The diagnosis of Kyaroikeidae is emended to accommodate the new genus

Mechanistic new insights of flavonols on neurodegenerative diseases

With a large and increasing elderly population, neurodegenerative diseases such as Parkinson’s disease (PD), Huntington disease (HD), Alzheimer’s disease (AD), Amyotrophic lateral sclerosis (ALS) and Multiple sclerosis (MS) have become a major and growing health problem. During the past few decades, the elderly population has grown 2.5 % every year. Unfortunately, there are no specific therapeutic remedies available to slow the onset or development of these diseases. An aging brain causes many pathophysiological changes and is the major risk factor for most of the neurodegenerative disorders. Polyphenolic compounds such as flavonols have shown therapeutic potential and can contribute to the treatment of these diseases. In this review, evidence for the beneficial neuroprotective effect of multiple flavonols is discussed and their multifactorial cellular pathways for the progressions of age-associated brain changes are identified. Moreover, the animal models of these diseases support the neuroprotective effect and target the potential of flavonols in the treatment of neurodegenerative diseases