Trdota predstavlja merilo odpornosti lesa proti prodiranju tršega telesa v njegovo notranjost in pogosto pogojuje uporabnost izbrane vrste lesa za določen namen uporabe. Poleg gostote, trdoto ...posamezne lesne vrste zelo pogojuje vlažnost lesa. V raziskavi smo ugotavljali trdoto lesa navadne smreke, uravnovešenega pri različnih relativnih zračnih vlažnostih. Meritve trdote smo izvedli z vtiskanjem kroglice v radialno površino lesa na inštrumentu za ugotavljanje mikromehanskih lastnosti materialov. Rezultati so pokazali, da se s poviševanjem vlažnosti lesa trdota lesa znižuje; vtisna trdota (HIT) in vtisni modul elastičnosti (EIT) sta tako pri absolutno suhem lesu znašala 110,8±11,7 MPa in 0,62±0,01 GPa, pri lesu z vlažnostjo točke nasičenja celičnih sten (29,4 %) pa 36,3±7,9 MPa in 0,40±0,05 GPa. Zniževanje trdote lesa s poviševanjem njegove vlažnosti se je pokazalo v povečevanju globine povzročenih vtisov in povečani hrapavosti površin vzorcev. Analiza lesnega tkiva z vrstičnim elektronskim mikroskopom je na območjih z vtisi razkrila usločenje celičnih sten lesa, njihovo gnetenje v lumne traheid, ter nastanek razpok znotraj celičnih sten.
Uvod: Lastnosti mentorja so za odnos med mentorjem, dijakom in študentom zdravstvene nege zelo pomembne. Namen raziskave je bil ugotoviti, katere lastnosti mentorjev so pomembne z vidika dijakov in ...študentov zdravstvene nege, in obratno, katere lastnosti mentorirancev, tj. dijakov oz. študentov, so pomembne z vidika mentorjev. Metode: Uporabljena je bila kvantitativna deskriptivna metoda raziskovanja. S spletnim anketnim vprašalnikom je bil anketiran 201 anketiranec, od tega 50 dijakov srednje zdravstvene šole (3. in 4. letnik), 97 študentov prve stopnje zdravstvene nege (2. in 3. letnik) ter 54 mentorjev v kliničnem okolju. Uporabljena je bila deskriptivna statistika, test hi-kvadrat ter metoda analize variance oz. analiza povprečij. Rezultati: Ugotovljeno je bilo, da mentorji menijo, da odnos med mentorirancem in mentorjem ni odvisen od mentorjeve starosti. Komunikacija je pomembna vsem trem skupinam anketirancev. Medsebojno spoštovanje je enako pomembno dijakom, študentom in mentorjem. Mentorjem je poleg dijakovega oz. študentovega spoštljivega odnosa najpomembnejše, da se dijak oz. študent zaveda svojih nalog in zadolžitev (x = 4,6). Najbolj zaželena lastnost mentorja je, da si vzame čas (x = 4,7) za dijaka oz. študenta ter da je organiziran in dostopen. Diskusija in zaključek: Med raziskovalnimi skupinami je opaziti razlike v dojemanju lastnosti in vrlin mentorjev. Vsem raziskovalnim skupinam je pomembna mentorjeva sposobnost komunikacije ter ustvarjanja kreativnega okolja.
Ta članek skuša odgovoriti na vprašanje, kateri besedni vrsti pripisati izraze, pri katerih opažamo del kategorialnih lastnosti medmeta in del kategorialnih lastnosti členka. Izziv je torej ...besednovrstna določitev tistih besed, ki nimajo stavčnočlenskih ustreznikov in jih ni mogoče enoznačno uvrstiti niti med medmete niti med členke.
Članek skuša odgovoriti na tri sklope vprašanj. (1) Kaj je medmet, kakšne podvrste medme - tov poznamo in kako jih uslovariti v eSSKJ? (2) Kakšni so medmeti in v katerih segmentnih in nadsegmentnih ...lastnostih se razlikujejo od preostalega besedja? Kakšna sta njihova pregibnost in besedotvorje? (3) Kaj so medmeti po izvoru?
Magnesium alloys have poor deformation properties at room temperature, and the application of an electric pulse current during deformation can improve the plastic-forming ability. In this study, the ...electric pulse rolling of AZ91D magnesium alloy specimens has been examined by changing the pulse output voltage. The results demonstrate that the best surface quality and lowest content (8.4 %) of the β-Mg17Al12 phase are achieved at an output voltage of 300 V. EBSD tests have revealed the lowest weave strength on {0002} and {100} at a pulse output voltage of 300 V, as well as the greatest enhancement of twinning. The maximum tensile strength was 165 MPa at an output voltage of 300 V, with a maximum elongation of 4.1 % at an output voltage of 200 V.
Reducing the salt, sugar and fat content of food is recognised worldwide as one of the strategies available for reducing the incidence of obesity and non-communicable diseases. The food industry has ...a major influence on achieving these goals by preserving intrinsic (chemical and sensory properties) and modifying extrinsic (food packaging and other external information) food attributes that can influence purchasing decisions. This article is a literature review of studies that analyse the influence of intrinsic and/or extrinsic attributes on consumer product preference and purchasing decisions.
A keyword search for relevant studies was conducted using Web of Science, an interdisciplinary electronic resource. Articles from other sources were also included and systematically reviewed.
The search string identified 266 results. Thirty-eight articles were included in the final analysis and coded according to intrinsic and extrinsic food attributes, reformulated nutrient, food category, condition, research methods, consumer response, study location and sample size. There are several authors investigating the effect of intrinsic rather than extrinsic product attributes. Most research deals with processed foods in the category of milk and dairy products, followed by sweetened fruit juices, meat products, sweets and bread. Salt content is the attribute most often reduced, followed by sugar and fat.
Consumers find it hard to swap potential health benefits for hedonic attributes. When evaluating products in expected conditions, they usually rate the reformulated product more highly than the conventional one, while in informed conditions they usually choose the regular product. When products are labelled with a traffic light or nutritional warnings, consumers opt for a reformulated product, even in informed conditions. This review highlights the heterogeneity between food groups, and the fact that many factors influence consumers' product preferences and purchasing decisions. The product should be analysed as a whole and tested in blind, expected and informed conditions, as each individual factor represents a phase of the consumer purchasing decision. The extent of nutrient reduction should be determined by calculating the difference threshold, and the industry should reformulate products gradually based on how consumers detect the reduction.
In this study, we optimized the preparation of 100–160 nm monodispersed SiO2 nanoparticles and, through doping, investigated their effects on the physical properties of a water-based acrylic-amino ...varnish. First, using a non-fixed point feeding technique based on the half-batch sol-gel method, we enhanced the yield of small-sized monodispersed SiO2 nanoparticles. To reduce the cost of production and organic-matter pollution, we assessed certain solution parameters including tetraethyl orthosilicate (TEOS), ethanol (ETOH) and ammonia in a single-reaction system. We found that the gloss, clarity, hardness, adhesion, and other physical properties of the acrylic-amino varnish were successfully enhanced through an addition of 1.2 % SiO2 nanoparticles.
In this study, the effects of Zr, Zn and Cu additions on the microstructure, room-temperature and high-temperature mechanical properties of an Mg-3Sn-1Ca alloy (from 25 °C to 250 °C) were studied. ...The results reveal that additions of Zr and Zn do not change the phase composition of the alloy, composed of CaMgSn and Mg2Sn phases. After the addition of Zn, the grains are significantly refined, the volume fraction of the second phase is increased and dispersed, and the Mg2Ca phase is precipitated. The grain refinement of Zr is better than that of Zn. After adding the Cu element, the Mg2Cu phase precipitates besides the CaMgSn phase. A comparison of mechanical properties shows that the alloy with Zr (TXK311) has the best mechanical properties at room temperature and high temperature, and the elongation of the TXK311 alloy can reach 68.3 % at 250 °C. The TXK311 alloy was comprehensively considered to find its optimum mechanical properties. The analysis shows that fine grains, a uniform phase distribution and texture play important roles in the deformation of the alloy.
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