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Number of results: 17
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Abstract

This work presents results of investigations on biotrickling filtration of air polluted with cyclohexane co-treated in binary, ternary and quaternary volatile organic compounds (VOCs) mixtures, including vapors of hexane, toluene and ethanol. The removal of cyclohexane from a gas mixture depends on the physicochemical properties of the co-treated VOCs and the lower the hydrophobicity of the VOC, the higher the removal efficiency of cyclohexane. In this work, the performance of biotrickling filters treating VOCs mixtures is discussed based on surface tension of trickling liquid for the first time. A mixed natural – synthetic packing for biotrickling filters was utilized, showing promising performance and limited maintenance requirements. Maximum elimination capacity of about 95 g/(m 3·h) of cyclohexane was reached for the total VOCs inlet loading of about 450 g/(m 3·h). This work presents also a novel approach of combining biological air treatment with management of a spent trickling liquid in the perspective of circular economy assumptions. The waste liquid phase was applied to the plant cultivation, showing a potential for e.g. enhanced production of energetic biomass or polluted soil phytoremediation.
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Authors and Affiliations

Piotr Rybarczyk
1
ORCID: ORCID
Bartosz Szulczyński
1
ORCID: ORCID
Dominik Dobrzyniewski
1
ORCID: ORCID
Karolina Kucharska
1
ORCID: ORCID
Jacek Gębicki
1
ORCID: ORCID

  1. Gdańsk University of Technology, Faculty of Chemistry, Department of Process Engineering and Chemical Technology, 80-233 Gdańsk, Narutowicza 11/12, Poland
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Abstract

Chemical and process engineering offers scientific tools for solving problems in the biomedical field, including drug delivery systems. This paper presents examples of analyzing the dynamics of dispersed systems (aerosols) in medical inhalers to establish a better relationship between the test evaluation results of these devices and the actual delivery of drugs to the lungs. This relationship is referred to as in vitro-in vivo correlation (IVIVC). It has been shown that in dry powder inhalers (DPls), the aerosolization process and drug release times are determined by the inhalation profile produced by the patient. It has also been shown that inspiratory flow affects the size distribution of aerosols generated in other inhalation devices (vibrating mesh nebulizers, VMNs), which is due to the evaporation of droplets after the aerosol is mixed witha dditional air taken in by the patient. The effects demonstrated in this work are overlooked in standard inhaler testing methods, leading to inaccurate information about the health benefits of aerosol therapy, thus limiting the development of improved drug delivery systems.
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Authors and Affiliations

Agata Dorosz
1
ORCID: ORCID
Arkadiusz Moskal
1
ORCID: ORCID
Tomasz R. Sosnowski
1
ORCID: ORCID

  1. Warsaw University of Technology, Faculty of Chemical and Process Engineering, Waryńskiego 1, 00-645 Warsaw, Poland
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Abstract

The paper discusses the application possibilities of ceramic foam in a thermal combustion process of a lean methane-air mixture. The experiments were done in a ceramic foam bed. The foam (Vukopor ® A) was made mainly of Al 2O 3. The foam samples were packed in a tubular reactor symmetrically placed in a laboratory furnace. It was assumed that the tested foam should have a surface close to the monolith surface area which was tested in a previous work (Pawlaczyk and Gosiewski, 2015). Pore density of the tested foam was 10 PPI. The tested air mixture contained 0.51 - 0.76 vol. % of methane. The results show that thermal methane oxidation in foam is possible in the acceptable range of temperatures. The combustion process in foam is characterized by similar ignition temperature to tests carried out in monolith, a more intense course, and better methane conversion at lower temperatures.
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Authors and Affiliations

Anna Pawlaczyk-Kurek
1
ORCID: ORCID
Aleksandra Janusz-Cygan
1
ORCID: ORCID

  1. Polish Academy of Sciences, Institute of Chemical Engineering, Baltycka 5, 44-100 Gliwice, Poland
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Abstract

In the presented work, the conditions of the high-temperature and mechanochemical method for the synthesis of compound Sm 5VO 10 and their influence on its physicochemical properties were studied. The following methods were used for the study: X-ray powder diffraction (XRD), differential thermal analysis (DTA), infrared spectroscopy (FTIR), ultraviolet and visible light spectroscopy (UV–VIS–DRS), scanning electron microscopy (SEM-EDX), and laser beam diffraction spectrometry (LDS). Based on the results, it was determined that the compound Sm 5VO 10 is thermally stable in air atmospheres up to 1475 °C, crystallises in a monoclinic system, and its structure is made up of oxygen VO 4 and SmO 8 polyhedra. The estimated energy gap value for nanometric, mechanochemically obtained Sm 5VO 10 was about 3.20 eV, and for the microcrystalline, obtained with the high-temperature method, was about 2.75 eV. The established physicochemical characterisation of Sm 5VO 10 initially showed that the compound could find potential applications, e.g. as a photocatalyst for water purification or as a component of new optoelectronic materials.
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Authors and Affiliations

Kamil Kwiatkowski
1
ORCID: ORCID
Mateusz Piz
1
ORCID: ORCID
Elżbieta Filipek
1
ORCID: ORCID

  1. West Pomeranian University of Technology in Szczecin, Faculty of Chemical Technology and Engineering, Piastów 42, 71-065 Szczecin, Poland
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Abstract

Simplified optimization method using the MATLAB function fminbnd was adopted to determine the optimal feed temperature (OFT) for an isothermal packed-bed reactor (PBR) performing hydrogen peroxide decomposition (HPD) by immobilized Terminox Ultra catalase (TUC). The feed temperature was determined to maximize (minimize) the average reactant conversion (reactant concentration) over a fixed period time at the reactor outlet. The optimization was based on material balance and rate equation for enzyme action and decay and considered the effect of mass-transfer limitations on the system behavior. In order to highlight the relevance and applicability of the work reported here, the case of optimality under isothermal operating conditions is considered and the practical example is worked out. Optimisation method under consideration shows that inappropriate selection of the feed temperature may lead to a decrease in the bioreactor productivity.
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Authors and Affiliations

Ireneusz Grubecki
1
ORCID: ORCID
Wirginia Tomczak
2
ORCID: ORCID

  1. Cracow University of Technology, Faculty of Chemical Engineering and Technology, Warszawska 24, 31-155 Cracow, Poland
  2. Bydgoszcz University of Science and Technology, Seminaryjna 3, 85-326 Bydgoszcz, Poland
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Abstract

Cosmetic emulsion bases containing extracts from natural plants were produced. The emulsifier was an aqueous solution of self-emulsifying base made from apricot kernel oil and soy lecithin, while the oil phase was based on coconut, almond or grape seed oils. In addition, mixtures enriched with vegetable glycerine were produced. It was found that for the emulsions with almond oil as the concentration of the oil phase increased, the value of the average Sauter diameter increased. In comparison, results for emulsions with coconut oil and emulsions with grapeseed oil did not give such a clear relationship. It was also shown that for stable emulsions, the self-emulsifying base of apricot kernel oil performed much better than soy lecithin. The addition of vegetable glycerine to the mixture resulted in a reduction of the average droplet diameter. Produced emulsions were also visually observed for 60 days to assess their stability and possible aging processes. In order to exclude the formation of microorganisms, periodic density control and microscopic examinations were carried out. The presence of microorganisms 30 in the analysed emulsion was evaluated using microscopic and culture techniques. No tarnish waso bserved on the surface of the samples, indicating the formation of mould, which can lead to poisoning and the development of allergies, respiratory diseases, liver diseases, ulcers, or bleeding in the intestines.
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Authors and Affiliations

Waldemar Szaferski
1
ORCID: ORCID
Piotr T. Mitkowski
1
ORCID: ORCID
Marcin Janczarek
1
ORCID: ORCID

  1. Poznan University of Technology, Institute of Chemical Technology and Engineering, Berdychowo 4, 60-965 Poznan, Poland
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Abstract

In recent years, European countries have experienced a noteworthy surge in the interest surrounding renewable energy sources, particularly the integration of photovoltaic (PV) panels with various types of heat pumps. This study aims to evaluate the energy performance of a grid19 connected hybrid installation, combining a PV array with an air-source heat pump (AHP), for domestic hot water preparation in a residential building located in Cracow, Poland. The primary focus of this evaluation is to assess the extent to which self-consumption (SC) of energy can be increased. The study utilizes Transient System Simulation Tool 18 software to construct and simulate various system models under different scenarios. These scenarios include building electricity consumption profiles, PV power systems, and the specified management of AHP. Analyses were conducted over a period of 1 year to assess the operational performance of the systems. In the considered installations, the differences in SC values between PV installation ranged from 9 to 25%. Notably, the highest SC values were observed during the winter months. AHP with operation control allows to obtain in some months of the year up to 35% higher value the SC parameter compared to systems without AHP. The highest annual 29 SC value recorded reached 83.9%. These findings highlight the crucial role of selecting an appropriate PV system size to maximize the SC parameter.
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Authors and Affiliations

Sebastian Pater
1
ORCID: ORCID

  1. Cracow University of Technology, Faculty of Chemical Engineering and Technology, Warszawska 24, 31-155 Cracow, Poland
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Abstract

The work motivation was to investigate in vitro system simulating drug release from Drug Eluting Stent (DES). The experiments were conducted in a custom designed unit simulating drug release from polymer covering DES in a simplified way. The active substance diffuses from a thin, internal annular layer of hydrogel (imitating “stent”) to the outer cylindrical layer of hydrogel (“artery wall”) and is at once drifted away by coaxially flowing solution (“blood”). The conducted research proved functionality of the experimental unit. The rate of mass transfer depends considerably on the mass driving force and on the affinity of substance-hydrogel. The volumetric flow rate and liquid viscosity did not affect the process significantly. The effective diffusion coefficient was calculated as a process parameter and then used in the other variants. Diffusion in hydrogel is the mechanism limiting the mass transfer in the examined system. For the first attempt, the diffusive model used in literature was employed. The provided calculations are consistent with experimental data and therefore show that despite its simplifications the model allows to estimate the amount of released substance.
In conclusion, the relative substance mass, changing over time, was estimated in the respective parts of the unit. The prospect of determining the relative mass of the substance appearing in the subsequent parts of the system over time provides the opportunity to adjust the respective process parameters, which will facilitate control over the rate of mass release.
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Authors and Affiliations

Anna Adach-Maciejewska
1
ORCID: ORCID
Klaudia Kopka
1

  1. Warsaw University of Technology, Faculty of Chemical and Process Engineering, Waryńskiego 1, 00-645 Warsaw, Poland
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Abstract

The influence of a fixed adsorption bed height on the adsorption process was studied using acetone, ethyl acetate, toluene, and n-butyl acetate as a gaseous adsorbate mixture. All experiments were conducted under the same gas flow and temperature conditions. Concentrations of adsorbates were monitored using gas chromatography with a flame ionization detector. Activated carbon WG-12 (Grand Activated Sp. z o.o) was selected as the adsorbent, and the following heights of the fixed adsorption bed were used: 0.8, 1.6, 3.2, and 4.8 cm. The results of the study allowed to deduce that as the height of the fixed adsorption bed increased, the degree of displacement of adsorbate molecules from the bed strengthened. In addition, it was found that both the bed breakthrough time increased linearly with a height rise of the fixed adsorption bed. The process carried out on a fixed adsorption bed with a height of 0.8 cm was characterized by an undeveloped mass transfer zone, as well as the complete displacement of the most volatile components (acetone and ethyl acetate). The utilization rate of the fixed adsorption bed also increased as the height of the adsorption bed went up. However, at a certain bed height, the bed breakthrough curves were formed and the adsorption capacity did not change significantly, solely the bed breakthrough time increased.
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Authors and Affiliations

Martyna Jurkiewicz
1
ORCID: ORCID
Marlena Musik
1
ORCID: ORCID
Robert Pełech
1
ORCID: ORCID

  1. West Pomeranian University of Technology in Szczecin, Faculty of Chemical Technology and Engineering, Department of Chemical Organic Technology and Polymeric Materials, Pułaskiego 10, 70-322 Szczecin, Poland
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Abstract

Despite its unique properties (biocompatibility and nontoxicity), chitin itself has limited application. Chitin is completely insoluble in most organic or inorganic solvents what can be beneficial when chitin is investigated as a support for chromatography or enzyme immobilization. These applications require the particles to have an extensive outer surface with a large number of reactive ligands. The increase in specific surface area of chitin particles can be performed by dissolution in ionic liquid and precipitation with water. To increase the number of reactive ligands (amine groups), deacetylation of the surface of chitin particles is necessary. The deacetylation process can be carried out by an enzymatic process with the enzyme, chitin deacetylase. In our investigation, 21 ionic liquids were used for chitin particle structure modification followed by enzymatic deacetylation. Results proved positive effect of modifications with ionic liquid on enzymatic deacetylation of the chitin surface with chitin deacetylase. For 12 samples the deacetylation gave an increase in number of active ligands in comparison to natural chitin. The best results were observed for [Bmim][Br], [Emim][Cl] and [MPpip][Ac]. That could be correlated with an increase in outer surface area by increasing porosity of particles or by structural changes in chitin particles.
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Authors and Affiliations

Małgorzata M. Jaworska
1
ORCID: ORCID
Dorota Biniaś
2
ORCID: ORCID
Katarzyna Dąbkowska-Susfał
1
ORCID: ORCID
Andrzej Górak
3
ORCID: ORCID

  1. Warsaw University of Technology, Faculty of Chemical and Process Engineering, Warynskiego 1, 00-645 Warsaw, Poland
  2. University of Bielsko-Biała, Faculty of Materials, Civil and Environmental Engineering, Department of Environmental Protection and Engineering, Willowa 2, 43-309 Bielsko-Biała, 9 Poland
  3. Faculty of Process Engineering and Environmental Protection, Lodz Technical University, ul. Wólczanska 213, 93-005 Lodz, Poland
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Abstract

This paper presents the development of a multiphase aerodynamic reactor designed for multi-component systems, focusing on precise catalyst dosing in the combustion chamber. The study aims to underscore the significance of this work by emphasizing the critical role of optimized operational conditions in enhancing the transportation of the modifier for combustion processes. Through comprehensive numerical simulations and experimental tests, this research explores the impact of parameters such as flow rates of the dosed substance and air, dosing nozzle outlet diameter, and conduit diameter on the flow rate and trajectory of the transported modifier. The findings highlight the importance of a minimum droplet diameter of 30 μm, preferably 50 μm, for proper delivery to the combustion chamber. This study not only identifies key differences between analyzed structures but also emphasizes the crucial role of these operational parameters in achieving optimal conditions for modifier transport.
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Authors and Affiliations

Marek Ochowiak
1 2
Zdzisław Bielecki
2 3
Andżelika Krupińska
1
Sylwia Włodarczak
1
Magdalena Matuszak
1

  1. Department of Chemical Engineering and Equipment, Poznan University of Technology, Pl. M. Sklodowska-Curie 5, 60-965 Poznan, Poland
  2. Kuncar S.A., Pszczyńska 167C, 43-175 Wyry, Poland
  3. Department of Automatic Control and Robotics, Silesian University of Technology, Akademicka 2A Str., 44-100 Gliwice, Poland
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Abstract

Fresh water is essential for life. More and more countries around the world are facing scarcity of drinking water, which affects over 50% of the global population. Due to human activity such as industrial development and the increasing greenhouse effect, the amount of drinking water is drastically decreasing. To address this issue, various methods of sea and brackish water desalination are used. In this study, an energy analysis (specific energy consumption, SEC) of two laboratory membrane processes, reverse osmosis (RO) and pervaporation (PV), was conducted. A model feed system saline water at 0.8, and 3.5% wt. NaCl was used. The efficiency and selectivity of membranes used in PV and RO were examined, and power of the devices was measured. The desalination processes were found to have a high retention factor (over 99%) for both PV and RO. For PV, the permeate fluxes were small but they increased with increasing feed flow rate, process temperature and salt content in the feed. The calculated SEC values for both laboratory processes ranged from 2 to 70 MWh/m 3. Lowering the process temperature, which consumes 30 to 60% of the total energy used in the PV process, can be an important factor in reducing energy consumption.
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Authors and Affiliations

Izabela Gortat
1
ORCID: ORCID
Joanna Marszałek
1
ORCID: ORCID
Paweł Wawrzyniak
1

  1. Lodz University of Technology, Faculty of Process and Environmental Engineering, Wólczańska 213, 93-005 Łódź, Poland
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Abstract

In this study, a stable and effective magnetically recoverable nanocatalyst was prepared by coating Fe 3O 4 nanoparticles with SiO 2, followed by functionalization with N-(2-aminoethyl)- 3-aminopropyltrimethoxysilane (AEPTMS) and produce Schiff base ligand to linkage Ru(OTf) 2 onto the surface. The nanocatalyst was characterized using various techniques such as FT-IR spectroscopy, SEM, TEM, and VSM to confirm its successful synthesis. The nanocatalyst was used for the trimethylsilylation of various alcohols (primary, secondary, and tertiary alcohols) using hexamethyldisilazane as a silylating agent in dichloromethane at room temperature. The reaction proceeded quickly with a protection time of only 90 seconds, which is a remarkable advantage of this nanocatalyst. The turnover frequency (TOF) values of the catalytic system were estimated to be 1869 h -1. The use of this nanocatalyst offers many advantages, such as excellent yield, catalyst reusability, high acidity, and strong magneticp roperties. These advantages make it a fascinating candidate for green chemistry principles. The simple reprocessing procedure and quick response times are also additional benefits of this nanocatalyst. Overall, this study provides a promising approach for the facile preparation of a stable and effective magnetically recoverable nanocatalyst that can be utilized for the trimethylsilylation of alcohols. The exceptional properties of this catalyst make it an attractive candidate for practical applications in the field of catalysis.
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Authors and Affiliations

Somayeh Mehdigholami
1
Esmaeil Koohestanian
2

  1. Young Researchers and Elite Club, Iranshahr Branch, Islamic Azad University, Iranshahr, Iran
  2. Department of Chemical Engineering, Iranshahr Branch, Islamic Azad University, Iranshahr, Iran
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Abstract

Biobased hydrogels are three-dimensional polymeric matrices with a unique high water-holding capacity, which are mainly obtained from polysaccharides and proteins. Such a variety of natural polymer structures offers a range of hydrogel products with interesting physicochemical and biological properties. Nowadays, these matrices are already used in many industrial and environmental fields, which is considered extremely important. Moreover, the literature on the subject is constantly expanding, especially in areas of scientific research. The main purpose of this article is to briefly review the current development of matrices composition and properties of hydrogels of natural origin, considered as functional platforms in three application areas, primarily in biocatalysis, nutrition and medicine. The description of individual issues in the present article is supported by examples of case studies described in our previously published research papers, as well as considered in current projects of our research group.
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Authors and Affiliations

Karolina Labus
1
ORCID: ORCID
Halina Maniak
1
ORCID: ORCID
Katarzyna Kołodzińska
1
Łukasz Radosiński
1
ORCID: ORCID

  1. Wrocław University of Science and Technology, Faculty of Chemistry, Department of Micro, Nano and Bioprocess Engineering, Norwida 4/6 50-373 Wrocław, Poland
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Abstract

Most of the existing toxic gas mitigation techniques have difficulty in practical implementation. More effective mitigation methods are required for handling hazardous gas releases in Chemical Process Industries (CPIs). One of the most hazardous chemicals is chlorine, an integral part of almost all chemical industries, especially chlor-alkali. This study examined a possible accidental spill of liquid chlorine from a chlorine storage area. Computational Fluid Dynamics, Process Hazard Analysis Software Tool (PHAST), and Probit analysis were combined to develop the overall effect and vulnerability models. The dispersion of chlorine vapors at wind speeds of 2, 3, and 4 m/s was analyzed, and the corresponding threat zones were plotted. Many public establishments of extreme vulnerability were located inside the threat zones. Offsite emergency planning guidelines are necessary for such conditions. Based on the results of the consequence analysis, a practical and cost-efficient IoT (Internet of Things) based mitigation system using physical barriers is proposed. The proposed mitigation system accounts for entrapment, continuous removal, and safe handling of the chlorine vapor from the release area. The proposed mitigation system can be implemented in all CPIs dealing with the production and storage of toxic gases. The outcome of this study can contribute to the development of Emergency Response Planning (ERP) guidelines for chlorine release.
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Authors and Affiliations

E Ahammed
1 2
AR Soman
1 3
PA Abdul Samad
1 2
B Varikkadinmel
4

  1. Department of Mechanical engineering, Government Engineering College, Thrissur, Kerala, India
  2. APJ Abdul Kalam Technological University, Kerala, India
  3. Department of Mechanical engineering, Government Engineering College, Idukki, Kerala, India
  4. Mechanical and Industrial engineering, Indian Institute of Technology, Roorkee, Uttarakhand, India
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Abstract

Current efforts are taken to increase resource efficiency, close material loops, and improve sustainable waste and by-products management. Thus, networking agro-food by-products andc onverting them into valuable products completely exhausting the potential of the raw material becomes significant. Model lignocellulosic and starch based biomass were subjected to pre-treatment with the application of acidic compounds, i.e. sulphuric (SA) and acetic (AA) acids. The response, i.e. total sugar content and derivatives content is investigated depending on variables changed during hydrolysis: concentration of acid, process duration, temperature and the size of the biomass particles. After saccharification, the hydrolysates were analysed via HPLC. Total reducing sugars concentration was in the range of 0.1 – 15.53 g/LAmong the substances present in the hydrolysates, protein, peptides, hydroxybenzyl acid (HA), 5-HMF, furfural (FF), vanillin (V), vanillic acid (VA), formic acid (FA) and levulinic acid (LA) were found in the range of 0.44 – 9.05 g/L and determined as total derivatives concentration. The aim of the study was to evaluate the measurable effects of the research and deliver information about the statistically important parameters for the process course and relations between the variables.
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Authors and Affiliations

Karolina Kucharska
1
ORCID: ORCID
Patrycja Makoś-Chełstowska
1
ORCID: ORCID
Edyta Słupek
1
ORCID: ORCID
Jacek Gębicki
1
ORCID: ORCID

  1. Gdansk University of Technology, Faculty of Chemistry, Department of Process Engineering and Chemical Technology, Narutowicza 11/12, 80-233 Gdansk, Poland
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Abstract

The paper aims to show a search method for optimal conditions of 3A, 13X, ZSM-5 zeolite thermal regeneration after adsorption from a liquid water-isopropanol mixture. Comparative TGA-DTG results for heating of wet zeolites with different structure and hydrophobicity showed characteristic effects corresponding to the optimal temperature of zeolite regeneration. The consequences of overheating and collapse of the 3A, 13X, ZSM-5 zeolite structure at temperatures of 850, 900, 1000 °C, respectively, were recorded with XRD method. Moreover, XRD and NIR/DRS tests of loaded and regenerated zeolite samples showed interaction of adsorbate and co-adsorbed water with adsorbent and revealed influence of adsorption and regeneration processes on the adsorbent structure. Investigations of the regeneration of the zeolite 3A bed after adsorption of water from the isopropanol solution in the temperature swing adsorption (TSA) process were carried out by heating the bed with inert gas at 250 °C and different purge gas streams in the range of 1.68–2.40 kg/h. Four stages of wet bed regeneration were distinguished, which corresponded to the effect observed during TGA-DTG tests. For each stage, the specific demand for purge gas and energy was determined depending on the gas stream and its minimum value of 2.16 kg/h was indicated.
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Authors and Affiliations

Piotr Tabero
1
ORCID: ORCID
Elżbieta Gabruś
2

  1. West Pomeranian University of Technology in Szczecin, Faculty of Chemical Technologyand Engineering, Department of Inorganic and Analytical Chemistry, Piastów 42, 71-065 Szczecin, Poland
  2. West Pomeranian University of Technology in Szczecin, Faculty of Chemical Technology and Engineering, Department of Chemicaland Process Engineering, Piastów 42, 71-065 Szczecin, Poland

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