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Cet article pose et tente de répondre à une question mille fois posée: celle de l’avenir de nos villes. Rétrospectivement on constate qu’à chaque fois le décalage entre le rêve et la réalité a été grand, entre utopie et régression. Nous prenons aussi le risque de cette question mais, ici, nous ne tracerons pas tant «des plans sur la comète» que nous n’essaierons de dégager, à partir d’une critique des dérives inquiétantes aujourd’hui constatées (renforcement des inégalités, spéculations financières), à peine atténuées par des lueurs d’espoir bien réel (essor de l’économie de la connaissance), les orientations et actions, ambitieuses parce que modestes et réalistes, qu’il faudrait engager pour rendre nos établissements humains vivables pour les générations qui nous suivront.

We conducted an avian count from November 2017 to October 2019. This qualitative and quantitative study at the level of an artificial environment, in the case of the palm grove d’El Hadjed in El Ménea, provides an objective inventory of the birds' diversity. A total of 48 species have been identified by researchers, distributed among nine orders and 19 families. The order Passeriformes is the most dominant, with 11 families and 36 species, or 75% of the recorded species. As for Muscicapidae, the Sylviidae are the best represented, with 11 and 5 species, respectively. Depending on phenological status, there are17 species of passage visitors (35.42%), 18 breeding species, of which 13 are residents (27.1%), and 5 are migratory species (10.42%). 12 species (25%) represent the winter visitor birds. At the national level, executive Fiat Algerian law (N°12-235) protects 8 species, or 16.67%, while Ordinance (06-05) protects one other species (Peregrine Falcon). Two species have an international status of "near threatened" (Lanius senator), while one species is classified as "vulnerable" (Streptopelia turtur). Shannon index values fluctuate between 2.91 bits (2018) and 2.99 bits (2019), and evenness index (E) values fluctuate between 0.56 bits (2018) and 0.62 bits (2019). [ABSTRACT FROM AUTHOR]

Copyright of African & Mediterranean Journal of Architecture & Urbanism (AMJAU) is the property of Ecole Nationale d'Architecture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Le Maroc célèbre les 100 ans de l'urbanisme au Maroc, mais une tradition urbaine y existe depuis bien longtemps à laquelle se sont ajoutés l'urbanisme colonial et une urbanisation récente. En plus d'un patrimoine architectural et paysager d'une grande richesse et d'autres atouts qui ne tombent pas dans la facilité de la rente pétrolière, on peut trouver aussi, notamment dans la culture de la densité propre à la ville marocaine, les ressources d'un "orbanisme", comme l'a suggéré Gaston Bardet, qui répond aux exigences d'un développement urbain durable...

Copyright of African & Mediterranean Journal of Architecture & Urbanism (AMJAU) is the property of Ecole Nationale d'Architecture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Naturaliste Canadien is the property of La Societe Provancher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Samba Dia Biosphere Reserve is rich an important plant resources. These make it face many threats. The most targeted species by populations is the palm (Borassus akeassii). The present study aims to characterize the woody vegetation of the reserve in terms of flora and structure in order to develop sustainable management strategies. To do this, 216 plots were inventoried fenced and peripheral area. Data were processed by univariate analysis technique. The analysis revealed a rich flora of 46 species, 36 genera belonging to 21 families. The Fabaceae, Anacardiaceae and Combretaceae are the most represented families. Borassus aethiopum Mart represents 32.921% in fenced area and 64.293% peripheral area of species marking tree character of the stand with densities of 29 and 7 individuals ha-1 respectively. These low densities noted are inherent to anthropogenic pressure and unfavorable climatic conditions. However, horizontal structure fits better with the polynomial function with a predominance of young individuals in fenced area (302 ha-1 stems) and individuals of multiple ages in peripheral area (33 ha-1 stems). The proliferation of Combretaceae especially in the fenced area is a negative sign. To reverse the trend, it is necessary to put in place a simple management plan for the maintenance and conservation of biodiversity. [ABSTRACT FROM AUTHOR]

• This paper presents the thermophysical properties of five commercial PCM • The thermal conductivity of the five PCM is 72-74% lower than water • The dynamic viscosity of the five PCM is from 2.2 to 8.3 times higher than water • The five PCM exhibit significantly lower heat transfer performance than water This paper presents the measurement of liquid phase density, thermal diffusivity, thermal conductivity, and dynamic viscosity of five commercial PCM (RT2HC, RT5HC, OM05-P, OM08, CrodaTherm9.5) in the temperature range 2 − 30 °C. The density of RT2HC, RT5HC, OM05-P is 23-24% lower than water, that of OM08 is 6% higher than water and that of CrodaTherm9.5 is 14% lower than water. The thermal diffusivity of RT2HC, RT5HC, OM05-P is 22-24% lower than water, that of OM08 is around a half of water and that of CrodaTherm9.5 is 38-40% lower than water. The thermal conductivity of the five PCM is 72-74% lower than water. The dynamic viscosity of RT2HC, RT5HC, OM05-P and OM08 is 2 − 3 times higher than water, and that of CrodaTherm9.5 is from 7.4 to 8.3 times higher than water. The five PCM are expected to provide convective heat transfer performance significantly lower than water. [ABSTRACT FROM AUTHOR]

Copyright of Ecoscience (Ecoscience) is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nouveau Praticien Vétérinaire Élevages et Santé is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Oil palm and its pollinators are native to Africa. Notwithstanding, it has been extensively cultivated outside its native range, so also has its pollinators been acquired and introduced. A concern, however is that most documentation on oil palm and its pollinators are non-indigenous, with little information of African origin commenting on their activities in Africa. Thus, a study on the insect pollinators of oil palm was carried out on two fruit forms: Dura and Tenera, (ages ten and seven, respectively), in Ghana. The aim was to understand how average monthly population density of the pollinators relates to one another, and to two bunch parameters (fruitset and fruit-to-bunch ratio). Nine species (all in the order Coleoptera) were consistently seen on the spikelets of anthesising male inflorescences, and eleven species on receptive female inflorescences. Six were of the Elaeidobius genus: E. kamerunicus, E. plagiatus, E. singularis, E. subvittatus, E. bilineatus, and Elaeidobius sp. 1 (unidentified species); two each were of the Microporum genus: M. congolenses, M. dispar, and the Prosoestus genus: P. scuptilis, P. minor; while one species was of either Atheta or Forficula. The pollinators were observed to be positively related, and to varying degree of significance. Fruitset level was acceptably high, indicating adequate pollinator population and efficient pollination. There was a positive relationship between population density of the pollinators and fruitset, and a negative relationship between the bunch parameters. A number of other insects were seldom observed around the male and female inflorescences; their role could not be defined. [ABSTRACT FROM AUTHOR]

Copyright of Ecoscience (Ecoscience) is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Silva Lusitana is the property of Unidade de Investigacao de Silvicultura e Productos Florestais and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An avifaunestic count was carried out between November 2017 and October 2020. This qualitative and quantitative study at the level of an artificial environment, in the case of the green band Noumérate in Ghardaïa Nord, for an objective inventory of the birds' diversity. Indeed, 86 species have been identified, belonging to 17 orders and 33 families. The order Passeriformes is the most dominant with 15 families and 56 species, or 44.12% of the recorded species. As for Muscicapidae, the Alaudidae, are the best represented with respectively 13 and 07 species. Depending on phenological Status, 43 species Passage Visitor (50%), 25 breeding species, of which 18 are Resident (20.93%) and 7 are migratory species (8.14%). The Winter Visitor birds are represented by 17 species (19.77%) and finally, only one species of bird bears the unknown phenological status. It should be noted that at the national level, 22 species have been identified, or 25.58% are protected by executive Fiat Algerian law (N°12-235). On the other hand, internationally, two species have been found to have "Near threatened" status (Meadow Pipit and Dartford Warbler) and only one species has "Vulnerable" status (European Turtle Dove). The hybrid Sparrow is the most dominant among all the species counted, with 30.9% in 2018 and 29.9% in 2019. Shannon index values fluctuate between 3.65 bits (2018) and 3.32 bits (2019) and evenness index (E) values are relatively constant between 2018 and 2019, equal to 0.65. [ABSTRACT FROM AUTHOR]

Understanding the mechanisms by which similar species coexist in sympatry is a major driver of ecological research. Niche partitioning and ecological plasticity can facilitate spatial and habitat use overlap between generalist and specialist species. Mouse lemurs (Microcebus spp.) are a highly speciose group of small primates that are endemic to the forests of Madagascar. In northwestern Madagascar, the relatively widespread M. murinus occurs sympatrically with the microendemic M. ravelobensis. We investigated spatial distributions and densities of these two species across a mangrove–dry forest habitat gradient in Mariarano commune. We used capture-mark-recapture techniques and nocturnal line transect surveys along six transects during June and July 2017. Spatial capture-recapture and distance sampling models were used to estimate lemur densities across habitat types. The congeners displayed differential patterns of spatial distribution and densities. Microcebus murinus was found in similar densities across all habitat types, while M. ravelobensis was found at much higher densities in dry forests compared with mangroves. This suggests that the generalist M. murinus uses a wider array of habitats more evenly than the specialist M. ravelobensis. Our study provides empirical evidence of how cryptic lemur species differ in their habitat use and distribution across an environmental gradient and provides new insights into their ecology in an understudied habitat. Lemurs are one of the most threatened groups of mammals in the world, and understanding how these species are distributed across different forest types is crucial for planning and implementing conservation measures to protect lemur habitat. [ABSTRACT FROM AUTHOR]

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This study focuses on the detection of the soil seed bank of Hassi Ben Abdellah's abandoned pivots (Ouargla) by the use of aqueous extracts of cultivated plant (Triticum durum and Hordeum sativum) and spontaneous (Moltkiopsis ciliata and Oudneya africana ). The identification of the potential flora of the seed bank. Showed that the flora that characterizes this bank of the seeds is of 06 vegetable species repaired on 03 families. The soil seed bank potential estimate was made by the semi-direct method. The density and the wealth vary from a treatment other on registré the strongest density and richness on the level of witness respectively 05 individuals, 04 species. The total wealth is of 05 species for the whole of the treatments the strongest is obtained by Oudneya africana. There is a specialization for Triticum durum, which has shown that poaceae (Bromus madritensis and Bromus rubens), as well as spontaneous species of Moltkiopsis ciliata, recorded 02 botanical families Poaceae (Bromus madritensis) and Amaranthaceae (Chenopodium mural). [ABSTRACT FROM AUTHOR]

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We conducted the first focused survey of nocturnal lemurs in the Mangabe reserve in order to assess their status within the reserve and provide recommendations for their conservation. We combined distance sampling and camera trapping to determine species occurrences and estimate their relative abundance within the reserve. The fieldwork was done in January to February 2018 in the northern and February to March 2019 in the southern part of the reserve. We surveyed 30 transects of one kilometer and each transect was visited three times. We installed eight camera traps; three in October 2017 and a further five were added in May 2018. Five species, Avahi laniger, Cheirogaleus major, Daubentonia madagascariensis, Microcebus lehilahytsara and Lepilemur mustelinus, were encountered and abundance differed between sites. D. madagascariensis and L. mustelinus are rare and should be prioritized for conservation actions in the future. The other lemur species including M. lehilahytsara, C. major and A. laniger can be used as key attractions for ecotourism within the reserve given their higher density. [ABSTRACT FROM AUTHOR]

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• A total of 87 (p, rho, T) data of R1123 were measured from 300 K to 430 K and up to 6.9 MPa. • A new equation of state was developed for R1123 based on the present data. • The new equation calculates all thermodynamic properties with reasonable accuracies. • The new equation shows good extrapolation at very high and low temperatures and high pressures. The (p, ρ, T) behavior of trifluoroethene (R1123) was investigated with the isochoric method. A total of 87 (p, ρ, T) data were measured along nine isochores (42, 98, 151, 197, 296, 493, 691, 790, and 888 kg · m − 3) at temperatures from 300 K to 430 K and pressures up to 6.9 MPa. The uncertainties in temperature are estimated to be within 10 mK below 380 K and 20 mK at higher temperatures, and the uncertainties in pressure are estimated to be within 1 kPa below 380 K and 2 kPa at higher temperatures. The estimated relative uncertainties in the density measurements are 0.15 % or less. A new Helmholtz energy equation of state was formulated based on the (p, ρ, T) data and recently published experimental data for the vapor pressure, liquid and vapor densities including those at saturation, vapor-phase sound speed, and ideal-gas isobaric heat capacity. The equation is applicable at temperatures from the triple-point temperature (195.15 K) to 480 K and pressures up to 20 MPa. Typical uncertainties in calculated properties are 0.1 % for vapor pressures, 0.1 % for liquid densities, and 0.2 % for vapor densities, except in the critical region where larger deviations up to about 1.5 % are sometimes observed in densities. The uncertainties in calculated vapor-phase sound speeds and ideal-gas isobaric heat capacities are 0.03 % and 1 %, respectively. The equation shows reasonable extrapolation behavior at extremely low and high temperatures, and at high pressures. [ABSTRACT FROM AUTHOR]

Le Québec, l’ensemble du Canada, voire l’Alaska ou la Russie, contiennent de vastes espaces nordiques inhabités. Cette affirmation, qui tombe sous le sens pour la majorité des Québécois et de leurs voisins anglophones, est pourtant lourde d’a priori discutables issus de la culture occidentale. En réalité, ces territoires sont soit occupés, parcourus ou nommés par les autochtones, depuis des siècles. Ces formes d’appropriation relativement légères, du moins en termes d’empreinte écologique, remettent en question le concept d’écoumène, notamment à cause de sa dimension binaire. Dans ce contexte, cette article vise à discuter des fondements du concept d’écoumène et, par ricochet, de nature sauvage (wilderness). Il apparaît évident que le terme écoumène est utilisé de manière réductrice et qu’il faille l’adapter pour décrire les divers modes possibles d’habiter le monde, notamment en milieu nordique. Au final, nous prônons la nécessaire reconnaissance des territoires de très faible densité, comme les espaces nordiques, afin d’entretenir des relations harmonieuses avec les autochtones.

• New thermodynamic data reported for mixtures of CO2 with HFCs and HFO-1234yf. • Data include vapour-liquid equilibrium, density and heat capacity measurements. • Accuracy of reference Helmholtz equations assessed for multi-component mixtures • Performance of Helmholtz equations in NIST's REFPROP 10 software package improved Measurements of the thermodynamic properties for a series of more environmentally-friendly refrigerant mixtures containing hydrofluorocarbons (HFCs), hydrofluoroolefins (HFOs), and carbon dioxide (CO 2) were conducted. These new property data help increase confidence in the design and simulation of refrigeration processes that use CO 2 + HFO + HFC refrigerant mixtures. The HFCs of interest were R32, R125, and R134a and the HFO tested was R1234yf. The measurements collected were prioritised to fill gaps in the available literature data. Vapour-liquid equilibrium plus liquid-phase density and heat capacity data were collected for different binary mixtures containing HFCs, HFOs and CO 2 , with the liquid phase measurements spanning (223 to 323) K and (1 to 5) MPa. The measured data, as well as data from the literature, were then used to tune the mixture parameters in the models used by NIST's REFPROP 10 software package to improve the prediction of thermodynamic properties for these fluids. To test the predictive capabilities of the models tuned to the binary mixtures, thermodynamic property data were also measured for four ternary mixtures and a five-component mixture of HFCs, HFOs and CO 2. The new models developed in this work significantly improved the root mean square deviations of the predicted properties for these multi-component mixtures: the most significant reductions were about a factor of two in density. [ABSTRACT FROM AUTHOR]

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Copyright of Dialogue: Canadian Philosophical Review is the property of Cambridge University Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

La régénération des huiles lubrifiantes peut être considérée comme une option privilégiée à la conservation des ressources énergétiques et à la réduction des dommages causés à l'environnement. Dans ce contexte, le présent travail a été élaboré en vue de démontrer la faisabilité de régénérer l’huile usagée Repsol32 utilisé comme lubrifiant dans le compresseur de synthèse d’ammoniac du complexe Fertial, Annaba. Le traitement à l’acide sulfurique a montré que pour un ratio VAcide/VHuile égal à 1/20 et une température de 40 °C, la viscosité cinématique et la teneur en eau de l’huile usagée sont nettement améliorées. Les valeurs des différents paramètres physicochimiques entrant dans la caractérisation de l’huile traitée (viscosité, humidité, indice de réfraction et densité) répondent bien aux normes d’utilisation des huiles minérales dans les processus de lubrification.

Radiotherapy is a treatment method performed using ionizing radiation on cancer patients either alone or with surgery and/or chemotherapy. Although modern radiotherapy techniques provide a significant advantage in protecting healthy tissues, it is inevitable that normal tissues are also located in the areas targeted by radiations. In this study, we aimed to examine the bone mineral density changes in bone structures commonly included in the irradiated area such as, L5 vertebra, sacrum, and femur heads, in patients who have received pelvic radiotherapy; and the relationship between these changes with radiation dose. Patients included in the study had been previously diagnosed with rectal cancer, which were operated or not. Preoperative or postoperative pelvic radiotherapy was planned for all patients. In terms of convenience when comparing with future scans, all densitometry and CT scans were performed with the same devices. Fifteen patients were included in the study. In order to determine the dose of radiation each identified area had taken after radiotherapy, the sacrum, L5 vertebra, bilateral femoral heads, and L1 regions were contoured in the CT scans in which treatment planning was done. Sagittal cross-sectional images were taken advantage of while these regions were being contoured. Bone mineral density was evaluated with CT and dual-energy X-ray absorptiometry before and after the treatment. The regions that have theoretically been exposed to irradiation, such as L5, sacrum, left to right femur were found to have significant difference in terms of bone density. According to CT evaluation, there was a significant decrease in bone intensity of L5, sacrum, left and right femurs. Dual-energy X-ray absorptiometry assessment revealed that the whole of the left femoral head, left femur neck and Ward's region were significantly affected by radiotherapy. However, there was no significant difference in the sacrum and L5 vertebra before and after radiotherapy. More accurate results could be achieved if the same study was conducted on a larger patient population, with a longer follow-up period. When the reduction in bone density is at maximum or a cure is likely in a long-term period, bone mineral density could be determined by measurements performed at regular intervals. [ABSTRACT FROM AUTHOR]

There are more than a thousand species of bamboo and some of these contain large amounts of fibres with attractive properties. However, the extraction of the fibres without damaging them is difficult, requiring energy and special equipment. One solution is to use the bamboo in the form of thin strips taken from fibre-rich regions of the plant, as done by the Cobratex company in an innovative process. These contain the fibres but they are protected from damage and keep their alignment. This paper presents the results from a study of bamboo strips, alone and in an infused composite. The influence of seawater immersion is investigated. The composite weight gain is high, around 25 %, but most of the water is in the natural canals of the wood. The influence of water is limited, a loss of 21 % in tensile modulus and 30 % in strength after saturation. These losses are smaller than for other natural fibre composites. [ABSTRACT FROM AUTHOR]

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Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revue Economique is the property of Fondation Nationale des Sciences Politiques and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Liquid-phase and vapour-phase densities are reported for the binary refrigerant mixtures (R125 + R1234ze(E)), (R134a + R1234ze(E)), (R143a + R1234ze(E)), (R1234ze(E) + R1234yf), (R125 + R1234yf), (R143a + R1234yf) and (R125 + R152a). The measurements span temperatures from (252 to 294) K and pressures from (0.8 to 4.2) MPa. Vapour-liquid equilibria (VLE) and liquid isobaric heat capacities are also reported for some mixtures. These measurements and previously published data were used to tune binary interaction parameters in existing Helmholtz energy models. Significant improvements in the predicted densities were achieved, for example the root mean squared relative deviation decreased from 0.33% to 0.021% for (R143a + R1234yf). The most significant improvement in the description of VLE occurred for (R1234yf + R1234ze(E)) where the root mean squared deviation in the predicted vapour phase compositions decreased from 0.010 to 0.00084 (a factor of 12). [ABSTRACT FROM AUTHOR]

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Highlights • Gaseous density data for R1234yf + R600a binary mixtures were measured. • Measurements were performed by a compact single-sinker densimeter. • A preliminary Helmholtz equation for R1234yf + R600a mixtures was developed. • Good agreement between the experimental and calculated values were found. • Correlation functions for azeotropic characteristics were developed. Abstract In this work, 101 gaseous densities of 2,3,3,3-tetrafluoroprop-1-ene (R1234yf) + isobutane (R600a) were carried out by using a compact single-sinker densimeter based on the well-known Archimedes' buoyancy principle. The experiment ranges in temperature, pressure, mole fraction of R1234yf and density are (270.105 to 300.214) K, (0.1014 to 0.4539) MPa, (0.2677 to 0.8630) and (3.207 to 20.523) kg m−3, with overall standard uncertainties of 5 mK, 200 Pa, 0.0005 and 0.10%, respectively. In addition, the multi-fluid approximations model combined with 11 mixing rules were employed to develop a preliminary Helmholtz free energy equation of state for R1234yf + R600a using the present and available experimental data. Good agreement between the experimental values and that calculated from the Helmholtz equation were found. Azeotropic characteristics was investigated at temperatures from (253.15 to 353.15) K, and correlation functions were developed for azeotropic component, pressure, saturated liquid and vapor densities. [ABSTRACT FROM AUTHOR]

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Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)