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1.
Org Process Res Dev ; 28(5): 1979-1989, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38783854

RESUMEN

Presented here is the design and performance of a coalescing liquid-liquid filter, based on low-cost and readily available meltblown nonwoven substrates for separation of immiscible phases. The performance of the coalescer was determined across three broad classes of fluid mixtures: (i) immiscible organic/aqueous systems, (ii) a surfactant laden organic/aqueous system with modification of the type of emulsion and interfacial surface tension through the addition of sodium chloride, and (iii) a water-acetone/toluene system. The first two classes demonstrated good performance of the equipment in effecting separation, including the separation of a complex emulsion system for which a membrane separator, operating through transport of a preferentially wetting fluid through the membrane, failed entirely. The third system was used to demonstrate the performance of the separator within a multistage liquid-liquid counterflow extraction system. The performance, robust nature, and scalability of coalescing filters should mean that this approach is routinely considered for liquid-liquid separations and extractions within the fine chemical and pharmaceutical industry.

2.
Anim Biosci ; 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38665070

RESUMEN

Objective: The objective of the current study was to find out the independent and interactive effects of prilled fat supplementation with protein on the production performance of early lactating Nili Ravi buffaloes. Methods: Sixteen early lactating buffaloes (36.75 ± 5.79 d in milk; mean ± SE) received 4 treatments in 4 × 4 Latin-square design according to 2 × 2 factorial arrangements. The dietary treatments were:1) LPLF = low protein low fat, 2) LPHF = low protein high fat, 3) HPLF = high protein low fat, and 4) HPHF = high protein high fat. The dietary treatments contained 2 protein (8.7 and 11.7% CP, crude protein) and fat levels (2.6 and 4.6% EE, ether extract) on a dry matter basis. Results: The yields of milk and fat increased with increasing protein and fat independently (p≤0.05). Energy-, protein-, and fat-corrected milk yields also increased with increasing protein and fat independently (p≤0.05). Increasing dietary protein increased the protein yield by 3.75% and lactose yield by 3.15% and increasing dietary fat supplies increased the fat contents by 3.93% (p≤0.05). Milk yield and fat-corrected milk to dry matter intake ratios were increased at high protein and high fat levels (p≤0.05). Milk nitrogen efficiency was unaffected by dietary fat (p>0.10), whereas it decreased with increasing protein supplies (p≤0.05). Plasma urea nitrogen and cholesterol were increased by increasing protein and fat levels, respectively (p≤0.05). The values of predicted methane production reduced with increasing dietary protein and fat. Conclusion: It is concluded that prilled fat and protein supplies increased milk and fat yield along with increased ratios of milk yield and fat-corrected milk yields to dry matter intake. However, no interaction was observed between prilled fat and protein supplementation for production parameters, body weight, BCS and blood metabolites. Predicted methane production decreased with increasing protein and fat levels.

3.
Int J Surg Case Rep ; 116: 109342, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38342030

RESUMEN

INTRODUCTION AND IMPORTANCE: Central giant cell tumor (CGCT) of bone is an uncommon yet locally aggressive neoplasm originating from undifferentiated mesenchymal cells in bone marrow. This case report explores a rare presentation in the maxilla extending to the mandible, emphasizing the complexity of CGCT management and the need for a multidisciplinary approach. CASE PRESENTATION: A 35-year-old female presented with a progressively enlarging non-tender, firm swelling on the left maxilla and a similar mandibular swelling. Paraesthesia of the left lower lip and chin accompanied the mandibular swelling. CT scans and 3D reconstructions revealed expansive osteolytic defects affecting the maxilla and mandible. Biochemical tests supported a central giant cell tumor diagnosis. Histopathology confirmed spindle cell proliferation and multinucleated giant cells in both lesions. Surgical intervention involved excision and reconstruction. A five-month follow-up showed no recurrence, affirming the treatment's success. CLINICAL DISCUSSION: Central giant cell tumors (CGCTs) of bone are primarily benign, arising from undifferentiated mesenchymal cells. While mostly benign, they carry a rare potential for malignancy. Diagnosis involves imaging (CT, MRI, bone scintigraphy) and confirmation through biopsy. Surgical resection is the standard treatment, with radiotherapy considered in challenging cases. Recurrence rates vary with the extent of surgical intervention. Alternative treatments like cryotherapy and chemotherapy show varying success. CONCLUSION: This case emphasizes the necessity of precise histopathological diagnosis for CGCT management. The intricate nature of maxillary involvement, coupled with mandibular association, mandates a multidisciplinary approach. Surgery, while the primary treatment, should be judiciously determined based on tumor characteristics and recurrence.

4.
Text Res J ; 93(21-22): 5017-5028, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37920184

RESUMEN

The release of fragmented fibers (FFs), including microplastics from textiles, during their service life is considered an established source of environmental pollution. The yarn structure is identified to affect the amount and length distribution profile of shed FFs from textiles. In the present work, the impact of yarn structures spun from 100% polyester staple fibers, using commercially relevant spun yarn technologies in the textile industry, on the release of FFs from textiles is studied. The bespoke woven fabric samples produced from three types of spun yarns, which include ring, airjet (air vortex) and rotor yarns, were subjected to an accelerated washing process, for up to five washes, to quantify shed FFs and their length distribution profile. The morphological shapes of FF ends associated with the nature of fiber damage were also investigated. The results demonstrated that airjet and rotor yarn structures had released 28% and 33% less mass of FFs, respectively, as compared to the ring yarn structure during the whole washing process. The length distribution profile identified that the ring yarn structure shed longer length FFs as compared to both airjet and rotor ones. The damaged ends highlight the importance of textile manufacturing processes on the generation of FFs. The results of this study give a better understanding of the yarn structural effect of commercially relevant technologies on shedding of FFs, which are released as a pollutant to the environment.

5.
Sci Rep ; 10(1): 12204, 2020 07 22.
Artículo en Inglés | MEDLINE | ID: mdl-32699221

RESUMEN

Microplastic pollution is ubiquitous in the marine environment and is ingested by numerous marine species. Sharks are an understudied group regarding their susceptibility to microplastic ingestion. Here, we provide evidence of ingestion of microplastic and other anthropogenic fibres in four demersal sharks species found in the waters of the United Kingdom and investigate whether body burdens of contamination vary according to species, sex or size. Sharks were collected from the North-East Atlantic. Stomachs and digestive tracts of 46 sharks of 4 species were examined and 67% of samples contained at least one contaminant particle. Although we acknowledge modest sample size, estimated particle burden increased with body size but did not vary systematically with sex or species. A total of 379 particles were identified, leading to median estimates ranging from 2 to 7.5 ingested contaminants per animal for the 4 species. The majority were fibrous in nature (95%) and blue (88%) or black (9%) in colour. A subsample of contaminants (N = 62) were subject to FT-IR spectroscopy and polymers identified as: synthetic cellulose (33.3%), polypropylene (25%), polyacrylamides (10%) and polyester (8.3%). The level of risk posed to shark species by this level of contamination is unknown. Nevertheless, this study presents the first empirical evidence and an important baseline for ingestion of microplastics and other anthropogenic fibres in native UK shark species and highlights the pervasive nature of these pollutants.

6.
Materials (Basel) ; 10(6)2017 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-28772977

RESUMEN

Reinforcement of flexible fibre reinforced plastic (FRP) composites with standard textile fibres is a potential low cost solution to less critical loading applications. The mechanical behaviour of FRPs based on mechanically bonded nonwoven preforms composed of either low or high modulus fibres in a thermoplastic polyurethane (TPU) matrix were compared following compression moulding. Nonwoven preform fibre compositions were selected from lyocell, polyethylene terephthalate (PET), polyamide (PA) as well as para-aramid fibres (polyphenylene terephthalamide; PPTA). Reinforcement with standard fibres manifold improved the tensile modulus and strength of the reinforced composites and the relationship between fibre, fabric and composite's mechanical properties was studied. The linear density of fibres and the punch density, a key process variable used to consolidate the nonwoven preform, were varied to study the influence on resulting FRP mechanical properties. In summary, increasing the strength and degree of consolidation of nonwoven preforms did not translate to an increase in the strength of resulting fibre reinforced TPU-composites. The TPU composite strength was mainly dependent upon constituent fibre stress-strain behaviour and fibre segment orientation distribution.

7.
Microsc Microanal ; 20(4): 1294-303, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24786513

RESUMEN

The orientation of fibers in assemblies such as nonwovens has a major influence on the anisotropy of properties of the bulk structure and is strongly influenced by the processes used to manufacture the fabric. To build a detailed understanding of a fabric's geometry and architecture it is important that fiber orientation in three dimensions is evaluated since out-of-plane orientations may also contribute to the physical properties of the fabric. In this study, a technique for measuring fiber segment orientation as proposed by Eberhardt and Clarke is implemented and experimentally studied based on analysis of X-ray computed microtomographic data. Fiber segment orientation distributions were extracted from volumetric X-ray microtomography data sets of hydroentangled nonwoven fabrics manufactured from parallel-laid, cross-laid, and air-laid webs. Spherical coordinates represented the orientation of individual fibers. Physical testing of the samples by means of zero-span tensile testing and z-directional tensile testing was employed to compare with the computed results.

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