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Two different methods are applied to evaluate the variability of wood ability for Kraft pulping of 25 poplar clones (1-year-old trees). The first one consists in pulping almost all of the wood of each analyzed tree ("macropulpings"). The second one is based on pulping very small wood samples, entire cross sections close to 1 g, taken at 50-cm height (micropulpings and paper microtests). This paper presents the results found separately with the two methods for the following parameters: pulp yield, Kappa (κ) index or permanganate index, and average fiber length. We observed that the evaluations of these parameters deduced by microtests are always well correlated with those obtained from pulping of the whole trees. Moreover, the two methods reveal that the suitability of poplar wood for Kraft pulping is under genetic control at age 1. But for each parameter (especially the ratio (κ index)/(pulping yield)2 and the average weighted fiber length), the differentiation of the clones is never exactly the same. Therefore, it is necessary to slightly modify the micropulping and microtests methodology to evaluate with better accuracy the pulp and paper properties of the whole trees.

Le thuya de Berbérie « Tetraclinis articulata Vahl », espèce résineuse endémique d’Afrique du Nord se trouve généralement sous forme de taillis. La valorisation de la biomasse de thuya, et en particulier de son bois peut être envisagée par la filière papetière par le biais d’une cuisson soude en présence d’anthraquinone (AQ). Le bois jeune de thuya (20 ans) se délignifie bien à l’aide d’une cuisson soude-anthraquinone dans les conditions habituellement appliquées aux résineux avec un temps total de cuisson de 145 min et une température de palier de 165 ◦C. Le rendement brut obtenu est égal à 43,3 % avec un indice Kappa de 33,6. Dans les mêmes conditions de cuisson, le bois âgé (60 ans) peut être lessivé mais se délignifie moins facilement., The coniferous trees of the thuya de Berbérie (Tetraclinis articulata Vahl), from the North Africa (Algeria) is commonly grown as a coppice stand. The biomass of thuya, and especially its wood, can be transformed in pulp by the paper and pulp industry throughout the soda cooking process with the help of the anthraquinone (AQ). The young wood (20 years-old) is well delignified in the soda–anthraquinone process, in the usual conditions applied to the resinous species, in the cooking time schedule of 145 min with the level of 165 ◦C of temperature. The pulp yield of raw material obtained is 43.3% (oven dried wood), with a kappa number of: 33.6. In the same cooking conditions, the mature wood (60 years-old) can be also treated, but with some lower delignification level.

This research work focuses on the development of a new process for the decontamination of municipal wastes incinerators fly ashes. The objective of this study was to evaluate different total and selective precipitation methods for metals removal from ash decontamination leachates. The tested options include 1) use of hydrated lime and caustic soda for selective (pH 5.0) and total (pH 8.5) metal precipitation; 2) addition of different chemicals (H3PO4, Na2S and FeCl3) in a pH range from 6.0 to 9.0. Fly ash decontamination assays using alkaline and acid washing steps were initially performed using optimal conditions previously established. Treated fly ashes respected the standards based on the TCLP leaching test for all studied metals and SPLP. Total metal precipitation tests carried out at pH 8.5 achieve removal yields for all metals > or = 90% using hydrated lime and > or = 83% using caustic soda. Selective precipitation tests alone at pH 5.0 show removal yields > or = 97% for Cr and between 75 and 87% for Al and Pb. Moreover, assays carried out using a stoechiometric addition of Na2S have allowed the separation of Cd (> or = 99%) and Zn (> or = 71%) as metal sulphides (CdS and ZnS). From an economical point of view, the most interesting option seems to be the leachates neutralization at pH 7.0 using Ca(OH)2 combined with the reuse of the treated leachates in the fly ash leaching steps. Metal precipitation cost at pH 7.0 has been estimated to be 22.7 CAN dollars tct-1 using Ca(OH)2, and 26.7 CAN dollars tct-1 using NaOH.

Cet article a pour objectifs : • de présenter un ensemble de bonnes pratiques qui peuvent être inspirées de l'application de la norme internationale ISO 10006 (2003) : « Systêmes de management de la qualité - Lignes directrices pour le management de la qualité dans les projets », dans l'organisation et la réalisation d'une recherche universitaire, débouchant sur une matrice de 54 éléments, • d'illustrer au travers de huit bonnes pratiques la maniêre de mettre en application sur le terrain une telle approche, • de positionner ces concepts dans la stratégie qualité globale de l'institution universitaire concernée, • de suggérer l'élaboration de 3 nouvelles normes internationales en relation avec les démarches qualité en recherche., The objectives of this article are: - to present a set of good practices which can be inspired by the application of the international standard ISO 10006 (2003): "Quality management systems - Guidelines for quality management in projects", in the organization and carrying out university research, leading to a matrix of 54 elements, - to illustrate through eight good practices the way to apply such an approach in the field, - to position these concepts in the overall quality strategy of the university institution concerned, to suggest the development of 3 new international standards in relation to quality approaches in research.

Summary — Consequences of the inclusion of sugar beet pulp in diets for early weaned and growing pigs. The effect of extrusion of wheat and of the inclusion of 6% of sugar beet pulp in a pelleted starter on the performance of the weaned piglet has been studied in two experiments. In the first experiment, 80 crossbred castrated male and female piglets weaned at 21 days of age raised individually y were used in a 2 x 2 factorial arrangement to compare their performance between weaning and 25 kg g live weight. Average feed intake was similar between treatments, but extrusion of wheat had no significant effect on growth performance and feed conversion ratio. The association of normal wheat with sugar beet pulp improved significantly growth rate (P < 0.02) and feed conversion ratio (P < 0.06), in particular during the period following immediatly weaning, ie, 193 vs 156 g/day and 193 vs 2.32, respectively. In the second experiment, 32 crossbred castrated piglets were used to evaluate faecal, then ileal digestibilities of dietary components. Extrusion did not improve digestibility. Ileal digestibility but not faecal digestibility of dry matter and energy was reduced (P < 0.001 ) by the inclusion of sugar beet pulp in the diet. Post-ileal digestibility of all dietary components was higher in animals fed fibrous diet. During the growing-finishing period between 25 and 100 kg live weight, the inclusion of a similar level of 6% of sugar beet pulp in a normal wheat based diet was tested. Piglets of the first experiment were randomly affected to one of the two diets taking into account their previous diet, sex and weight. The average daily gain for the whole period was slighly but not significantly reduced and feed conversion ratio was unchanged in animals receiving sugar beet pulp. However, feed conversion ratio expressed as digeatible energy per kg of body weight gain was reduced in animals receiving beet pulp in their diet. At slaughter, the percentage of lean meat was improved from 52.8 to 54.0% (P < 0.05) as a consequence of a linear decrease in the backfat thickness (P < 0.05) of carcasses of animals receiving sugar beet pulp. No difference in the weight of lean cuts was observed but the use of sugar beet pulp decreased significantly the weight of fat cuts (P < 0.01 It was suggested that for a similar nitrogen retention a reduction in the digestible energy intake reduces the deposition of fatty tissues but the total amount of lean meat in the carcass was not affected by the inclusion of sugar beet in the diet.

Fibrous fractions were prepared from sugar beet pulp (RF) by sequential extractions with potassium oxalate, 0.05 M hydrochloric acid at 85°C and 0.05 m sodium hydroxide at 4°C. The overall composition, polysaccharide structure and some physico-chemical properties (cation exchange capacity, CEC; water holding capacity, WHC; swelling) of each fraction were determined. RF was mostly composed of carbohydrates (66.3 %) with minor amounts of ash, proteins and lignin. The main polysaccharides were highly methylated and acetylated pectins, cellulose and arabinans. The oxalate residue (82.1 % of RF) exhibited only minute differences from RF whereas the acidic and alkaline residues, accounting for 42.8 % and 35.5 % of RF, respectively, were enriched in cellulose and hemicelluloses (xylans, xyloglucans, mannans) and mostly devoid of pectins and arabinans. CEC and WHC of fractions were closely related to the content of unmethylated galacturonic acid residues. The influence of the ionic form of ionisable groups was demonstrated, the Na+ form giving the highest WHC. The ionic strength of the medium can reduce the WHC, especially in the case of the acid and alkali-extracted fibres.

The influence of adding a fibre rich concentrate feed (wheat bran or beet pulp) to a hay-based diet (orchard grass-lucerne mixture; 50/50) upon the rate of passage of digesta of these two fractions (hay and concentrate) was measured in three groups of 8 adult doe rabbits (White New Zealand x California). The three diets composed of either 90% hay, or hay + bran or hay + pulp were offered at two levels of feeding, i.e. ad libitum and 2/3 ad libitum. The retention time of the two main fractions was measured by means of two tracers, i.e. ytterbium-169 bound to hay and cerium-141 to bran or pulp. Animals fed on the 90% hay diet excreted more than 90% of the tracer during the first 24 h. The mean retention time (MRT) of this diet was the shortest (on an average 14.8 h). The addition of pulp or bran increased the MRT of the diet by 2 and 4 h, respectively. Feed restriction led to a 5 to 7 h earlier period of caecotrophy with a subsequent lengthening of the MRT by 2 to 4 h according to groups. The two hay + "concentrate" diets gave almost the same 169Yb and 141Ce excretion curves. Thus, the mean retention time seems to be the same for digesta from hay and "concentrate" (non significant deviations).

The effect of adding a fibre-rich concentrate (wheat bran or beet pulp) to a hay-based diet (cook's foot-lucerne: 50/50) on the apparent digestibility of diets was measured in three groups of 8 adult doe rabbits (New-Zealand White X Californian). Diet composition was as follows: 90% hay only (diet F), hay + bran (diet FS) or hay + pulp (diet FP). Two levels of feeding were tested: ad libitum and 2/3 of ad libitum intake. Addition of wheat bran and especially of beet pulp led to a significant increase in the apparent digestibility of the whole diet. Our results confirm the high digestibility of cell-wall constituents of beet pulp: the apparent digestibility coefficient of hemicellulose in diet FP reached 60% (versus 23% for diet F) and that of cellulose 45% (21% for diet F). Wheat bran supplied digestible hemicellulose (ADC = 48% for diet FS) while the apparent digestibility of bran cellulose was not higher than that of hay (ADC = 22%). This digestive interaction between raw material was accompanied by an interaction with the digestive transit. The less digestible diet (diet F) exhibited the shortest mean residence time (MRT). However, diet FS exhibited the longest residence time whereas it was less digestible than diet FP. These results suggest that, in the rabbit, wheat bran is a transit-regulator as already observed in other species. Measuring apparent digestibility between the 10th and the 16th day of the feed restriction was too early for our doe rabbits. Values measured were not significantly different from those obtained during ad libitum feeding, although the MRT of diets was longer during restricted feeding.