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1.
ACS Omega ; 9(9): 10090-10098, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38463304

RESUMO

In this study, we report the successful synthesis of a phenol-formaldehyde-pyrazole (PF-PYZ) compound through the surface functionalization of phenol-formaldehyde (PF) with pyrazole (PYZ). The resulting mixture was subjected to comprehensive characterization using a range of analytical techniques, including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The newly synthesized PF-PYZ material effectively removes Cr(VI) ions. Notably, a substantial elimination efficiency of 96% was achieved after just 60 min of contact time. The strategic incorporation of pyrazole (PYZ) as the principal functionalizing agent contributed to this exceptional performance. Notably, the functionalized PYZ sites were strategically positioned on the surface of PF, rendering them readily accessible to metal ions. Through rigorous testing, the optimal sorption capacity of PF-PYZ for Cr(VI) ions was quantified at 0.872 mmol Cr(VI)/g, highlighting the material's superior adsorption capabilities. The practical utility of PF-PYZ was further established through a reusability test, which demonstrated that the chromate capacity remained remarkably stable at 0.724 mequiv Cr(VI)/g over 20 consecutive cycles. This resilience underscores the robustness of the resin, indicating its potential for repeated regeneration and reuse without a significant capacity loss. Our work presents a novel approach to functionalizing phenol-formaldehyde with pyrazole, creating PF-PYZ, a highly efficient material for removing Cr(VI) ions. The compound's facile synthesis, exceptional removal performance, and excellent reusability collectively underscore its promising potential for various water treatments, especially oil field and environmental remediation applications.

2.
Int J Occup Saf Ergon ; 28(4): 2193-2201, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34581248

RESUMO

Timber harvesting processes, especially motor-manual felling, are hazardous to forestry workers' health and safety. The purpose of this study is to examine forestry workers' mental safety models (at the supervisor and operator levels) using the Nordic safety climate questionnaire. This study also examines how operators and their families perceive workplace risks (dread and unknown risk factors). The safety climate analysis revealed that supervisors misunderstand management safety priority, competence, empowerment and justice. Additionally, this study found that operators do not yet prioritize safety. There was a lack of safety communication and operators' skepticism about the current safety system. These findings highlight the critical importance of implementing safety measures into operators' work environments. The risk perception analysis revealed that family members had a greater risk aversion to dread risk factors than operators. As a result, we see a possibility for family members to act as safety-net figures, bolstering the operators' safety values.


Assuntos
Saúde Ocupacional , Cultura Organizacional , Humanos , Árvores , Agricultura Florestal , Indonésia , Local de Trabalho , Percepção
3.
Sci Total Environ ; 634: 1385-1397, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29710638

RESUMO

The effective implementation of sustainable forest management depends largely on carrying out forest operations in a sustainable manner. Climate change, as well as the increasing demand for forest products, requires a re-thinking of forest operations in terms of sustainability. In this context, it is important to understand the major driving factors for the future development of forest operations that promote economic, environmental and social well-being. The main objective of this paper is to identify important issues concerning forest operations and to propose a new paradigm towards sustainability in a changing climate, work and environmental conditions. Previously developed concepts of forest operations are reviewed, and a newly developed concept - Sustainable Forest Operations (SFO), is presented. Five key performance areas to ensure the sustainability of forest operations include: (i) environment; (ii) ergonomics; (iii) economics; (iv) quality optimization of products and production; and (v) people and society. Practical field examples are presented to demonstrate how these five interconnected principles are relevant to achieving sustainability, namely profit and wood quality maximization, ecological benefits, climate change mitigation, carbon sequestration, and forest workers' health and safety. The new concept of SFO provides integrated perspectives and approaches to effectively address ongoing and foreseeable challenges the global forest communities face, while balancing forest operations performance across economic, environmental and social sustainability. In this new concept, we emphasize the role of wood as a renewable and environmentally friendly material, and forest workers' safety and utilization efficiency and waste management as additional key elements of sustainability.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais/métodos , Agricultura Florestal/métodos , Florestas
4.
Med Princ Pract ; 17(3): 233-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18408393

RESUMO

OBJECTIVE: To estimate the serum levels of soluble intercellular adhesion molecule-1 (s-ICAM-1) in children newly diagnosed with lymphoma and to correlate levels of s-ICAM-1 in lymphoma patients with clinical stage, pathological types, clinical and laboratory data and patient outcome. SUBJECTS AND METHODS: Thirty-five children with newly-diagnosed malignant lymphoma (Non-Hodgkin's lymphoma, NHL: 23), Hodgkin's disease (HD: 12), and 8 apparently healthy subjects of matched age and sex taken as a control group were studied. For the patients and control group, the following tests were performed: complete blood count, and the following biochemical investigations: liver function tests, lactate dehydrogenase (LDH), and soluble ICAM-1 estimation using ELISA. In addition, for patients, pathological examination of lymph node biopsy for pathological grading, bone marrow aspiration and biopsy were done. Patients were observed for over 12 months or until death. RESULTS: Serum ICAM-1 increased more in HD and NHL than in the control group (p < 0.000); also s-ICAM-1 increased in advanced stages and high-grade NHL (p < 0.008, 0.04, respectively). LDH levels were higher in patients compared to controls (p < 0.000). There was a positive correlation between high levels of s-ICAM-1 and increased levels of LDH in HD (r = 0.72, p < 0.008) and a positive correlation between high levels of s-ICAM-1 and increased ALT in NHL patients. A positive correlation between s-ICAM-1 levels and the presence of B symptoms in HD and NHL, and a positive correlation between elevated s-ICAM-1 levels and worse outcome in HD and NHL were detected. CONCLUSIONS: The data indicate that in children with malignant lymphoma, high serum levels of ICAM-1 correlated with tumor aggressiveness, and quantification of s-ICAM-1 levels may identify a subgroup of children with worse prognosis. Therefore, detection of s-ICAM-1 levels in children with malignant lymphoma might represent an additional disease-associated marker for use in the clinical management of the patients.


Assuntos
Biomarcadores Tumorais/sangue , Doença de Hodgkin/sangue , Molécula 1 de Adesão Intercelular/sangue , Linfoma não Hodgkin/sangue , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Progressão da Doença , Feminino , Humanos , Lactente , Masculino , Prognóstico
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