Lime mud (LM), whose main component is calcium carbonate, is a byproduct in the pulp and papermaking industry. For non-wood pulping processes, large amounts of LM are produced every year, and a portion of them has been used as a paper filler. However, LM significantly lowers alkyl ketene dimer (AKD) sizing efficiency when added to paper. In this study, LM slurry was first pre-flocculated using some commonly used wet-end additives; then, the pre-flocculated LM was added to the pulp for handsheet preparation. The effect of LM pre-flocculation on AKD sizing efficiency was investigated by means of Cobb60 value, contact angle, and sizing reversion. Finally, the AKD adsorption, particle size, BET surface area, BJH pore volume, and zeta potential of native and pre-flocculated LM were measured. It was found that handsheets filled with preflocculated LM had lower Cobb60 values and larger contact angles compared to handsheets filled with native LM. The sizing reversion was also alleviated to a certain extent. This was probably because the BET surface area and BJH pore volume of pre-flocculated LM were lower than native LM and the zeta potential was higher than native LM, which led to a much less adsorption of AKD. Thus, AKD sizing efficiency was significantly improved.

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Cationic polyacrylamide with different molecular weights were used to preflocculate the lime mud (LM) before it was added to the paper stock for handsheet preparation. The particle sizes, f potential, and morphology of the unpreflocculated and resulting preflocculated LM were studied. We found that high-molecular-weight cationic polyacrylamide (H-CPAM) led to larger LM flocs with a more positive f potential. The scanning electron microscopy images indicated that the morphological structure of the filler hardly changed during the preflocculation process. The effects of the preflocculation on the filler retention and paper properties were also investigated. The results show that the handsheets filled with preflocculated LM had better hydrophobicity and strength properties compared to handsheets filled with unpreflocculated LM, especially for H-CPAM-preflocculated LM. The paper formation was also improved, and the optical properties nearly remained the same. In addition, the LM preflocculated with H-CPAM had the highest filler retention. At a filler loading of 30%, the filler retention of the H-CPAM-preflocculated LM was higher than 86; it was less than 82.5% in other cases.

A southern population (S) from Xiushui County (29°1′N, 114°4′E) and a northern population (N) from Shenyang city (41°48′N, 123°23′E) of the cabbage beetle, Colaphellus bowringi vary greatly in their life-history traits, and may serve as an excellent model with which to study the inheritance of life-history traits. In the present study, we performed intraspecific hybridization using the two populations, comparing the key life-history traits (fecundity, development time, body weight, growth rate, and sexual size dimorphism (SDD)) between the two populations (S♀ × S♂ and N♀ × N♂) and their two hybrid populations (S♀ × N♂ and N♀ × S♂ populations) at 19, 22, 25, and 28°C. Our results showed that there were significant differences in life-history traits between the two parental populations, with the S population having a significantly higher fecundity, shorter larval development time, larger body weight, higher growth rate, and greater weight loss during metamorphosis than the N population at almost all temperatures. However, these life-history traits in the two hybrid populations were intermediate between those of their parents. The life-history traits in the S × N and N × S populations more closely resembled those of the maternal S population and N population, respectively, showing maternal effects. Weight loss for both sexes was highest in the S population, followed by the S × N, N × S, and N populations at all temperatures, suggesting that larger pupae lost more weight during metamorphosis. The changes in SSD with temperature were similar between the S and the S × N populations and between the N and the N × S populations, also suggesting a maternal effect. Overall, our results showed no drastic effect of hybridization on C. bowringi, being neither negative (hybrid inferiority) nor positive (heterosis). Rather, the phenotypes of hybrids were intermediate between the phenotypes of their parents.

The lagged time on goodwill is a common phenomenon in the process of quality improvement, which plays an important role in making quality strategy of supply chain. With increasing public attention to quality, supply chain quality management has become a research focus in recent years. This paper probes into the lagged time of quality on goodwill under the competitive environment of retailers and constructs a lagged differential equation of quality on goodwill based on the Nerlove–Arrow model. The results indicate that the optimal goodwill and quality are higher under centralized decision-making than under decentralized decision-making; however, whether or not the profit of the entire supply chain is higher under centralized decision-making depends on the span of the lagged time. Under decentralized decision-making, the lagged time of product quality on goodwill is favorable to retailers but unfavorable to manufacturers and vice versa. Therefore, when competition is low, a supply chain tends to adopt centralized decision-making. When competition is intense, it is appropriate for a supply chain to adopt decentralized decision-making. In conclusion, this paper analyzes the effects of the lagged time on the optimal quality level and supply chain profit as well as the effect of the competition coefficient on research findings concerning supply chain profit under centralized and decentralized decision-making to verify the relevant conclusions of this paper.