ACTION DE LA QUANTITÉ JOURNALIÈRE DE LUMIÈRE SUR LA FLORAISON, LE POIDS SEC ET LA TENEUR EN EAU DE QUELQUES PLANTES DE JOURS COURTS ET DE JOURS LONGS

Abstract— Experiments were carried on in the Liège Phytotron for two years to discover what reactions could be obtained when both short-day and long-day plants were placed in the same light energy per day (light intensity × daily light duration in various combinations) and receiving respectively 8 or 16 hr light per day. It was observed that both types of plants give parallel dry weight curves in both long-day and short-day, but this happens only during the vegetative state following germination.
Differences occur in those dry weight curves in short-day plants and also in long-day plants when cultivated under inductive photoperiodic light and induced to flower.
In these suitable light conditions, their dry weight increased compared with that of plants left in a non-inductive photoperiodic fight.
The evolution of tissue water content (stems, leaves, flowers), expressed as water % of the dry weight, is also interesting to observe in the same experimental environments. This evolution plays an important physiological part in flower formation, as has been shown before by R. Bouillenne.
Both types of plants cultivated in their respective non-inductive light point out a very simple curve of water content. First a rapid increase of water into the tissues during the first 10 days after germination; then from this maximum, the curve goes down regularly and slowly till a constant low level.
However, in inductive light exposure, water content percentage curves are really different for both types of species. Considering the same daily value of light energy given in each case, it is possible to conclude that the induction of flower does not depend on the daily light quantity but on something else which is connected with the photoperiodism.
These fluctuations of the water content will be investigated.     

Water-soluble cellulose derivatives prepared by the action of solutions of nitrogen dioxide in dimethylformamide

Cellulose derivatives soluble in water and in dilute alkali were prepared by dissolving a bleached sulfite pulp in solutions of nitrogen dioxide in dimethylformamide (DMF) and heating at 70–90°C for 1–3 hr. No cellulose oxidation was detected. Nitrite esters and apparently also, nitrate esters, were formed with degrees of substitution (DS) ranging from 0.18 to 0.55 and with nitrogen contents ranging from 1.47 to 4.32%. Solution viscosities in water increased with increasing nitrogen content. The degree of polymerization (DP) decreased rapidly in the initial stages of the reaction followed by a slow, gradual decrease with increasing reaction times.     

Influence of Different Processing Treatments on the Detectability of Nucleic Acid and Protein Targets in Transgenic Soybean Meal

Influences of dry heating, wet heating, and extrusion on the degradation of DNA and protein from transgenic soybean meal (TSM) were analyzed using qualitative PCR, quantitative real-time PCR (qPCR), indirect enzyme-linked immunosorbent assay (iELISA), and Western blot. The 414-bp Lectin gene was thoroughly degraded after dry heating between 75 and 90 °C for 30 min, wet heating, and extrusion at 165 °C with 39 % moisture content. The 483-bp CP4-EPSPS gene was not detected after dry heating, wet heating, and extrusion at 120 °C with 39 % moisture content. The degradation ratios of both Lectin and CP4-EPSPS genes increased from 0.4 to 92.1 % and 6.1 to 84.0 % as temperatures rose from 90 to 165 °C. iELISA results of the extruded TSM showed that the CP4-EPSPS protein content was reduced from 4.19 to 0.54 % as temperatures rose from 90 to 150 °C and was not detectable at 165 °C. Western blot results also showed the degradation of CP4-CPSPS protein after extrusion. Our results showed that temperature played an essential role in DNA and protein degradation, and the content of genetically modified organism (GMO) products may be changed after processing and could not reflect the initial content of the products.     

Pressurized Hot Water Extraction and Bio-Hydrogels Formulation with Aristotelia chilensis [Mol.] Stuntz Leaves

Aristotelia chilensis is a plant rich in phenolics and other bioactive compounds. Their leaves are discarded as waste in the maqui berry industry. A new application of these wastes is intended by the recovery of bioactive compounds using pressurized hot water extraction with conventional or microwave heating. Both technologies have been selected for their green character regarding the type of solvent and the high efficiency in shorter operation times. Extractions were performed in the temperature range 140–200 °C with a solid/liquid ratio of 1:15 (w:w). The extracts’ total phenolic content, antioxidant capacity, and saccharides content obtained with both heating methods were measured. Additionally, the thermo-rheological properties of the gelling matrix enriched with these extracts were analyzed. Optimum conditions for lyophilized extracts were found with conventional heating, at 140 °C and 20 min extraction; 250.0 mg GAE/g dry extract and 1321.5 mg Trolox/g dry extract. Close to optimum performance was achieved with microwave heating in a fraction of the time (5 min) at 160 °C (extraction), yielding extracts with 231.9 mg GAE/g dry extract of total phenolics and antiradical capacity equivalent to 1176.3 mg Trolox/g dry extract. Slightly higher antioxidant values were identified for spray-dried extracts (between 5% for phenolic content and 2.5% for antioxidant capacity). The extracts obtained with both heating methods at 200 °C contained more than 20% oligosaccharides, primarily glucose. All the formulated gelling matrices enriched with the obtained extracts displayed intermediate gel strength properties. The tested technologies efficiently recovered highly active antioxidant extracts, rich in polyphenolics, and valuable for formulating gelling matrices with potential applicability in foods and other products.     

Analytical applications of condensed phosphoric acid-I Determination of ferrous and total iron in iron ores after decomposition with condensed phosphoric acid

A simple method is described for the determination of ferrous and total iron in iron ores. Iron ores are dissolved by condensed phosphoric acid (CPA) very rapidly without any tedious and time-consuming manipulations such as elimination of silica and filtration. Under the proposed conditions (amount of sample 100 mg, amount of CPA added 10 g, heating temperature 290 degrees , heating time 30 min), magnetite, limonite and hematite are completely dissolved. The iron content can be determined in the presence of condensed phosphoric acid by titration with dichromate solution, if a slight modification is made. The total iron in iron ores, determined by the present method, is in agreement with that found by the JIS method. The ferrous iron in iron ores can be determined by dissolving the samples with CPA in a nitrogen atmosphere and titrating with dichromate solution. Chelatometric titration of iron after solvent extraction with MIBK from solutions prepared by use of CPA is found to be accurate for samples such as pyrite cinder. The ability of CPA to dissolve various materials has been investigated.     

蚕丝丝素中色氨酸含量及其在丝素纤维中的径向分布研究

通过双波长分光光度法和对二甲氨基苯甲醛显色法研究桑蚕春茧内、中、外各茧层丝素中的色氨酸含量和色氨酸在丝素纤维中的径向分布状况 ,并探讨了光、热处理后蚕丝丝素中色氨酸含量的变化 .结果表明 ,外、中、内各茧层丝素的色氨酸含量不一致 ,由外至内各茧层丝素中色氨酸含量依次降低 ;色氨酸在丝素纤维的径向分布不均一 ,呈现色氨酸在易溶落的最外表面层含量最多 ,次表层相对较少 ,中间层较多 ,而内层最少的分布状态 ;光或热处理均会破坏丝素中色氨酸 ,使色氨酸含量明显下降 .     

Determination of phosphorus in waste water by EDXRF

Summary In a method developed for the determination of phosphorus in aqueous solutions, phosphorus was changed to the phosphate form, coprecipitated with hydrated iron(III) oxide, bound with activated charcoal and measured by EDXRF. The detection limit was 0.89 mg P/g activated charcoal. The method was used to determine the total phosphorus content of a waste water sample from a paper mill. Investigation of two sample destruction methods, dry ashing/HCl digestion and persulphate oxidation, showed the former to be more suitable for our purpose.     

The glass transition and crystallization of ball milled cellulose

Samples of ball milled cellulose were prepared by ball milling pulps from eucalyptus and softwood (spruce/pine). Water sorption isotherms were obtained by both dynamic vapor sorption and equilibration over saturated salt solutions, in the water content range of 5–42% db (db = dry basis; water as a % age of total solids). Dynamic mechanical analysis using a pocket technique showed a water content dependent thermal transition occurring at the same temperature for the two pulp samples, which was interpreted as a glass transition. Fitting the data to a Couchman–Karasz relationship predicted a value for T _g of the dry cellulose of approximately 478 K, which was similar to values previously reported for other dry polysaccharides. No clear glass transition could be observed calorimetrically, although an endotherm at approximately 333 K was measured, which in polymers is normally attributed to enthalpic relaxation, however the lack of dependence of this endotherm on water content suggests that the melting of some weak associations, such as residual hydrogen bonds, could be a more credible explanation. An exotherm was also observed on heating, which was dependent on water content and which was attributed to partial crystallization of the cellulose. This was confirmed by Wide angle X-ray diffraction and cross polarization magic angle spinning ¹³C NMR (CPMAS NMR). The recrystallisation was predominantly to form I of cellulose. This was thought to be caused by a small amount of residual form I (probably less than 5%) acting as a template for the crystallizing material. Differential scanning calorimetry reheat curves showed the appearance of freezable water for water contents higher than 20%, as a result of a transfer of water to the amorphous phase following crystallization. The increase in cellulose rigidity following crystallization was also confirmed by CPMAS NMR relaxation. Low resolution proton NMR T ₂ relaxation suggested the presence of proton water/cellulose exchange, which was active at water contents of 20% and above.     

Temperature dependent wide angle X-ray diffraction studies on the crystalline transition in water saturated and dry polyamide 6/66 copolymer

The crystalline transition in water saturated and dry polyamide 6/66 copolymer (ratio 4:1 by mol) was investigated by means of temperature dependent wide angle X-ray diffraction (WAXD). The polyamide 6/66 copolymer (PA6/66) exhibits a poorly developed α-phase at room temperature after being cooled down from the melt. Uptake of water improves the crystalline structure by mobilizing the amorphous phase, thus facilitating chain relaxation in the crystalline phase. Upon heating, the effect of the glass transition on the change of the crystal lattice constants is seen. Further heating leads to a gradual crystalline transition from the α-phase to a pseudohexagonal phase. Different from the behavior in polyamide 6, this pseudohexagonal phase does not further transform to a high temperature α′-phase before melting. The delay of the crystalline transition in the water saturated PA6/66--as compared to the dry material can be understood as a result of the better ordered crystalline structure in it.     

Studies of pyrolysis and air heating of rayon by inverse gas chromatography

Inverse gas chromatography using water probing at 110°C was carried out to characterize rayon yarns after prior heating at 200 and 250°C in both inert (nitrogen) and oxidative (dry air) atmospheres for successively longer time intervals. During the early stages of heating in either atmosphere, the affinity of the rayon for water drops rapidly. However, whereas continued heating in N₂ results in a further loss of activity, data have been obtained showing that after an initial period yarns heated in air at 250°C exhibit an increasing attraction for water even while losing more weight.     

Pipeline transport of biomass

The cost of transporting wood chips by truck and by pipeline as a water slurry was determined. In a practical application of field delivery by truck of biomass to a pipeline inlet, the pipeline will only be economical at large capacity (>0.5 million dry t/yr for a one-way pipeline, and >1.25 million dry t/yr for a two-way pipeline that returns the carrier fluid to the pipeline inlet), and at medium to long distances (>75 km [one-way] and >470 km [two-way] at a capacity of 2 million dry t/yr). Mixed hardwood and softwood chips in western Canada rise in moisture level from about 50% to 67% when transported in water; the loss in lower heating value (LHV) would preclude the use of water slurry pipelines for direct combustion applications. The same chips, when transported in a heavy gas oil, take up as much as 50% oil by weight and result in a fuel that is >30% oil on mass basis and is about two-thirds oil on a thermal basis. Uptake of water by straw during slurry transport is so extreme that it has effectively no LHV. Pipeline-delivered biomass could be used in processes that do not produce contained water as a vapor, such as supercritical water gasification.     

高压微波制备Pt／C催化剂的工艺研究

利用高压微波消解仪密闭带压、升温速率可控的特点,选择XC-72碳黑为载体,乙二醇为碳黑分散溶剂和还原剂,研究反应温度、升温速率、水含量、Pt含量及表面活性剂等工艺条件对Pt粒子尺寸及其分散度的影响．研究结果表明,快速升温到190℃、控制反应体系中水含量和Pt含量等工艺条件,可以得到Pt粒子平均粒径小于3．1nm的Pt／C催化剂,且Pt粒子分布均匀,无团聚．     

Phase distribution of the products of radiation and postradiation distillation of cellulose

A comparison of the postradiation dry distillation of cellulose and its distillation in the mode of electron-beam radiation heating has shown that irradiation reduces the yield of char and water. Preirradiation of cellulose at doses of 0.2–2.2 MGy stimulates a monotonic increase in the proportion of total organic products in the condensate distilled off during postradiation dry distillation, reducing the proportion of water by one third. Effective distillation of cellulose in the radiation heating mode is observed at a dose rate above ∼1 kGy/s. The condensate distilled off at 1.5–2.5 kGy/s is composed of organic compounds by ∼90% and is characterized by a high density (up to 1.33 g/cm³) and a high refractive index (up to 1.4690).     

Densitometric thin-layer chromatographic determination of aescin in a herbal medicinal product containing Aesculus and Vitis dry extracts

A thin-layer chromatographic (TLC) method is developed to analyze the total saponin content, also referred to as the aescin content, in a herbal medicinal product (HMP) containing two dry extracts in capsules. The capsules contain 250 mg of Aesculus hippocastanum dry extract, 120 mg of Vitis vinifera dry extract and 50mg of excipients. After a purification step using C(18) solid phase extraction (SPE) cartridges, the samples are analyzed on a silica-gel HPTLC plate with the upper layer of a mixture of acetic acid/water/butanol (10/40/50 v/v/v) as the mobile phase. Spots are visualized by spraying with anisaldehyde reagent and heating the plate for 5-10 min (100-105 degrees C) and measured at a wavelength of 535 nm. This method, applicable for the quality control and stability investigation of both the Aesculus dry extract and HMP capsules thereof containing Vitis dry extract in combination with the Aesculus dry extract, is validated according to the International Conference on Harmonization (ICH) guidelines. The proposed assay method is specific for aescin in the presence of Vitis dry extract and formulation excipients. Analysis of stressed samples in forced degradation tests proves the method to be applicable for stability evaluation. The standard aescin curve is linear (r > 0.99) over a concentration range of 0.16-0.80 microg/spot. Recovery from the HMP capsules is statistically equal to 100%. The precision of the method with respect to time and concentration is acceptable, with relative standard deviation (RSD) values of 1.28 and 1.49%, respectively.     

Influence of gas media on the thermal decomposition of second valence iron sulphates

FeSO₄·H₂O and FeSO₄ represent the second valence of iron sulphates. Number of studies has been done to understand formation of intermediate sulphates like FeOHSO₄ and Fe₂O(SO₄)₂, representing the oxidation of Fe²⁺ to Fe³⁺. At selected temperatures, both the thermo-dynamical equilibrium in the Fe–S–O system and the formation of the crystal structures in the solid phase are controlled by the partial pressure of water vapour and oxygen in the gas phase. The effects of the temperature and the partial pressure of gas components on the solid-phase content are demonstrated by phase diagrams. The study puts the accent on the influence of oxygen content in gas environment on processes of thermal decomposition of FeSO₄·H₂O and FeSO₄. At three quantities of oxygen content—0% (100% Ar), 21% (dry air) and 100% (pure O₂) the processes of oxidation and formatting metastable iron sulphates were examined by several experimental techniques. The thermal decomposition of samples was investigated by TG–DTG–DTA method in the temperature range 293–1400 K. Partial pressure of water vapour was determined by the quantity of water released from dehydration process of FeSO₄·H₂O. Infrared spectroscopy, Mössbauer spectroscopy and X-Ray powder diffraction method were used for identification of the new formed solid structures and for characterization of the content of the iron sulphates with different valencies of iron. The experimental data and their analyses give the possibility to determine the different stages of decomposition, related to the formation of intermediates. Depending on gas environment, the basic relationships for reaction kinetics is drawn. It is demonstrated on that correlation exists between the kinetic’s parameters and the content of oxygen in the gas phase.     

Physical and chemical properties of bio-oils from microwave pyrolysis of corn stover

This study was aimed to understand the physical and chemical properties of pyrolytic bio-oils produced from microwave pyrolysis of corn stover regarding their potential use as gas turbine and home heating fuels. The ash content, solids content, pH, heating value, minerals, elemental ratio, moisture content, and viscosity of the bio-oils were determined. The water content was approx 15.2 wt%, solids content 0.22 wt%, alkali metal content 12 parts per million, dynamic viscosity 185 mPa.s at 40 degrees C, and gross high heating value 17.5 MJ/kg for a typical bio-oil produced. Our aging tests showed that the viscosity and water content increased and phase separation occurred during the storage at different temperatures. Adding methanol and/or ethanol to the bio-oils reduced the viscosity and slowed down the increase in viscosity and water content during the storage. Blending of methanol or ethanol with the bio-oils may be a simple and cost-effective approach to making the pyrolytic bio-oils into a stable gas turbine or home heating fuels.     

Application of thermomagnetometry to corrosion studies of archaeological iron

Summary Thermomagnetometry has been applied to mineralized archaeological iron samples and samples from accelerated corrosion tests. It has successfully quantified the degree of corrosion, measured by the loss of iron, as well as the amount of magnetite formed and water held in the corrosion and adhered soil layers. Thermomagnetometry, thermogravimetric analysis and differential scanning calorimetry have been applied to the reported corrosion products from archaeological iron. Fourier transform infra-red and Raman spectroscopies and X-ray diffraction analyses were undertaken on the residues and at intermediate heating stages, where the thermal analyses indicated, to identify the reaction products.     

Classification of commercial wines from the Canary Islands (Spain) by chemometric techniques using metallic contents

Eleven elements, K, Na, Ca, Mg, Fe, Cu, Zn, Mn, Sr, Li and Rb, were determined in dry and sweet wines bearing the denominations of origin of El Hierro, La Palma and Lanzarote islands (Canary Islands, Spain). Analyses were performed by flame atomic absorption spectrophotometry, with the exceptions of lithium and rubidium for which flame atomic emission spectrophotometry was used. Sweet wines from La Palma were elaborated as naturally sweet with over-ripe grapes and significant differences were found in all the analysed elements with the exceptions of sodium, iron and rubidium with regard to dry wines from the same island. Contrarily, sweet wines from Lanzarote elaborated with grapes in a similar ripening state to dry wines did not present significant differences between them with the exception of strontium, the content of which was greater in dry wines. Among the three islands, significant differences in mean content were found with the exceptions of iron and copper. Cluster analysis and principal component analysis show differences in wines according to the island of origin and the ripening state of the grapes. Linear discriminant analysis using rubidium, sodium, manganese and strontium, the four most discriminant elements, gave 100% recognition ability and 95.6% prediction ability. The sensitivity and specificity obtained using soft independent modelling of class analogy (SIMCA) as a modelling multivariate technique were both 100% for El Hierro and Lanzarote, and 100 and 95%, respectively, for La Palma. The modelling and discriminant capacities of the different metals were also studied.     

Effect of Continuous and Discontinuous Microwave-Assisted Heating on Starch-Derived Dietary Fiber Production

Dietary fiber can be obtained by dextrinization, which occurs while heating starch in the presence of acids. During dextrinization, depolymerization, transglycosylation, and repolymerization occur, leading to structural changes responsible for increasing resistance to starch enzymatic digestion. The conventional dextrinization time can be decreased by using microwave-assisted heating. The main objective of this study was to obtain dietary fiber from acidified potato starch using continuous and discontinuous microwave-assisted heating and to investigate the structure and physicochemical properties of the resulting dextrins. Dextrins were characterized by water solubility, dextrose equivalent, and color parameters (L* a* b*). Total dietary fiber content was measured according to the AOAC 2009.01 method. Structural and morphological changes were determined by means of SEM, XRD, DSC, and GC-MS analyses. Microwave-assisted dextrinization of potato starch led to light yellow to brownish products with increased solubility in water and diminished crystallinity and gelatinization enthalpy. Dextrinization products contained glycosidic linkages and branched residues not present in native starch, indicative of its conversion into dietary fiber. Thus, microwave-assisted heating can induce structural changes in potato starch, originating products with a high level of dietary fiber content.