Water-soluble polyphosphonate-based bottlebrush copolymers via aqueous ring-opening metathesis polymerization

Ring-opening metathesis polymerization (ROMP) is a versatile method for synthesizing complex macromolecules from various functional monomers. In this work, we report the synthesis of water-soluble and degradable bottlebrush polymers, based on polyphosphoesters (PPEs) via ROMP. First, PPE-macromonomers were synthesized via organocatalytic anionic ring-opening polymerization of 2-ethyl-2-oxo-1,3,2-dioxaphospholane using N-(hydroxyethyl)-cis-5-norbornene-exo-2,3-dicarboximide as the initiator and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) as the catalyst. The resulting norbornene-based macromonomers had degrees of polymerization (DPn) ranging from 25 to 243 and narrow molar mass dispersity (Đ ≤ 1.10). Subsequently, these macromonomers were used in ROMP with the Grubbs 3rd-generation bispyridyl complex (Ru-G3) to produce a library of well-defined bottlebrush polymers. The ROMP was carried out either in dioxane or in aqueous conditions, resulting in well-defined and water-soluble bottlebrush PPEs. Furthermore, a two-step protocol was employed to synthesize double hydrophilic diblock bottlebrush copolymers via ROMP in water at neutral pH-values. This general protocol enabled the direct combination of PPEs with ROMP to synthesize well-defined bottlebrush polymers and block copolymers in water. Degradation of the PPE side chains was proven resulting in low molar mass degradation products only. The biocompatible and biodegradable nature of PPEs makes this pathway promising for designing novel biomedical drug carriers or viscosity modifiers, as well as many other potential applications.</p

The effect of brown seaweed (Sargassum ilicifolium) powder on western white leg shrimp

The effects of substitution of seaweed, Sargassum ilicifolium, by replacing protein resources, in Litopenaeus vannamei diets was studied. It was carried out by incorporation of raw powdered seaweed at three levels, 0% as control treatment, 5% (C), 10% (B) and 15% (A) each with four replications in isoprotein, (33%) and isocaloric (355kcal.100^-1) diets. Binder properties of seaweeds in different diet pellets were evaluated. In laboratory conditions, 480 shrimp juveniles (initial weight=3 gram) acclimated in 16 plastic tanks, fed 4% of their biomass daily. During the 45 day digestibility experiment, biometric indices were measured at 15 day intervals to assess the growth performances. Based on physicochemical analysis of water at 2 day intervals, effective parameters were maintained at a required range for the wellbeing of the shrimp during the experiment. Results of the experiment show that Sargassum sp. can be used as a binder in shrimp feed ingredients with significant differences between treatment pellet stability and water absorbance percent in sea water. Although initial biomass, SGR and survival rate showed no differences between treatments, but final biomass, biomass gain, FCR, shrimp flesh color and cholesterol levels revealed significant differences between treatments (p<0.05). The diet with the highest level of seaweed (A) showed not only the best growth performances, survival rate, change in the flesh color desirable to the consumers and decreased cholesterol level in shrimp, but also has the best binder property for shrimp pellet making

Water-stable fluorinated metal&#8211;organic frameworks (F-MOFs) with hydrophobic properties as efficient and highly active heterogeneous catalysts in aqueous solution

Two new fluorinated metal-organic frameworks [Zn-2(hfipbb)(2)(4-bpdh)]0.5DMF (TMU-55) and [Zn-2(hfipbb)(2)(4-bpdb)]2DMF (HTMU-55) have been solvothermally synthesized by the reaction of two linear N-containing ligands as pillars (4-bpdb = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene and 4-bpdh = 2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene), and a flexible V-shaped fluorinated linker, H(2)hfipbb = 4,4-(hexafluoroisopropylidene) bis(benzoic acid). The two compounds were characterized by different techniques such as X-ray crystallography, powder X-ray diffraction (PXRD), infrared spectroscopy (IR), contact angle (CA), thermogravimetry (TGA), field emission scanning electron microscopy (FE-SEM), inductively coupled plasma (ICP), and Brunauer-Emmett-Teller (BET) surface area analysis. Both compounds are structurally similar and exhibit three dimensional (3D) coordination frameworks with hydrophobic properties. The catalytic activity of these isoreticular F-MOFs as efficient base heterogeneous catalysts toward the Knoevenagel condensation reaction was tested and compared to each other. TMU-55 and HTMU-55 exhibited good catalytic activity (with a minimum amount of catalyst, 2.5 mg (0.5 mol%), and the shortest time, 5 min) in water as a green solvent with excellent conversions. Also, the results were considerably higher in comparison with most of the values given in the literature for this reaction at ambient temperature. The remarkable catalytic performance of TMU-55 and HTMU-55 in water can be attributed to the presence of hydrophobic fluoro groups near the basic reaction center in the F-MOFs. These catalysts maintain their crystalline frameworks after the reaction and are easily recovered and reused at least for three cycles without significant loss in their catalytic activity. Furthermore, the conversion of benzaldehyde can be kept over 95% while the selectivity of the Knoevenagel reaction is kept at 100%

Dibromidobis(pyrazine-2-carboxamide-κN 4)zinc

The title complex, [ZnBr2(C5H5N3O)2], shows crystallographic mirror symmetry with the Zn atom and the two bromine ligands located on the mirror plane. The Zn atom is four-coordinated in a distorted tetra­hedral fashion by two N atoms from two pyrazine-2-carboxamide ligands and two Br atoms. Only one of the amino H atoms is involved in an N—H⋯O hydrogen bond. The crystal packing is further stabilized by weak N—H⋯N and C—H⋯O inter­actions

Dichloridobis(pyrazine-2-carboxamide-κN 4)zinc(II)

In the crystal of the title compound, [ZnCl2(C5H5N3O)2], the mol­ecule has m symmetry, with the ZnII cation and Cl− anions located on the mirror plane. The ZnII cation is coordinated by two Cl− anions and two pyrazine-2-carboxamide ligands in a distorted ZnCl2N2 tetra­hedral geometry. The two pyrazine rings are nearly perpendicular to each other [dihedral angle = 86.61 (10)°]. Inter­molecular N—H⋯O and N—H⋯N hydrogen bonds and weak C—H⋯O inter­actions stabilize the crystal packing

catena-Poly[[[aqua­(pyrazine-2-carboxamide-κ2 N 1,O)zinc]-μ-pyrazine-2-carboxamide-κ3 N 1,O:N 4] dinitrate]

In the crystal of the title compound, {[Zn(C5H5N3O)2(H2O)](NO3)2}n, the ZnII cation is N,O-chelated by two pyrazine-2-carboxamide (PCA) ligands and is further coordinated by one water mol­ecule and by one pyrazine-N atom from an adjacent PCA ligand in a distorted ZnN3O3 octa­hedral geometry. One of the two independent PCA ligands bridges two ZnII cations, forming a zigzag polymeric chain running along the c axis. In the crystal, the NO3 − anions link to the chain via O—H⋯O and N—H⋯O hydrogen bonding. Weak inter­molecular C—H⋯O inter­actions also occur

The effectiveness of artificial reefs for rehabilitation and production of fisheries in Iran

An artificial Reef is a fabricated, underwater structure, typically built for promoting marine life in areas of generally featureless bottom. Creating artificial reefs began from 2000 in southern provinces in Iran. This study has surveyed about the Bushehr and Khozestan states. The objective is to determine the effectiveness of artificial reefs in attracting and enhancing the production different aquatics through increasing of fish assemblage and fishery. The performance of artificial reefs deployed off the coast of the Persian Gulf in 10 to 15m, was evaluated. The reefs comprised of seven artificial and one control (natural) statistical tests plan in three replicates. Three types of artificial reefs were used in this study. That two were designed reefs and one was not designed or used material. The experimental plan consisted (i) Reef ball (R), designed hemispherical shaped; (ii) Laneh Mahi (L), designed pyramid shaped; (iii) Used material (U); (iv) mixed (RL); (v) mixed (RU); (vi) mixed (LU); (vii) mixed (RLU); and (viii) control site (CS). Trap nets and under-water visual census surveys were adopted for seasonal sampling of fish aggregation. Results of statistical analysis using ANOVA and T-test of the mean Catch per Unit Effort (CPUE) showed significant difference (p<0.05) in term of computing number of fish for aggregation of fishes. The study has concluded that reef deployments have influenced favorably the fish communities and fish harvests. Therefore, the artificial reefs, especially the mixed RLU, are appropriate tools for future fishing enhancement in the Persian Gulf of Iran

An investigation effect of seaweeds as shrimp -feed ingredient for growth performance of Litopenaeus vannamei

In this project, the nutritional effects of Sargassum illicifolium Chabahar bay-Oman Sea, on growth and survival rates of whiteleg shrimp (Litopenaeus vannamei) were studied. The seaweed collected from 6 coastal area, rinsed, dried, powdered and measured the nutritional values in laboratory for surveying statistically. According to the high nutritional value of Tis coastal seaweed, this variate seaweed powder, replaced with protein resources (fish meal and Soy and Wheat) of whiteleg shrimp feed which was formulated by Havorash feed factory of Boshehr in four treatments (A: as control without any replacement) B: with 5%, C: 10 % and D: 15% seaweed replacement, each with three replicates in order to obtain isonitrogenus 33% CP., and Isocaloric (13% fat and 15% carbohydrate) feed. The weighed milled ingredients were carefully mixed using a laboratory food mixer. The mixtures were primed with 30% hot water to yield a suitable pulp. Wet diets were made into 2 mm pellet size and dried at 40 °C in a drying cabinet and maintained in standard condition which was used according to daily need shrimp, calculated by each 10 days biometry. Water stability and absorbtion capacity of the pellets in sea water were measured and compared statistically. Juvenile shrimps (Initial body weight =3 g) brought from Jask hatchery, acclimazed for one week in Chabahar hatchery condition and feeding daily 3-5% body weight. Abiotical parameters and weight and length biometrics were measured two days and 10 days, respectively. After 45 days and final biometry, FCR, CF, SGR, caracas analysis, muscle colourimetery with HPLC were done, tasted with pp Plot for determining the parametric data and statistically differences using one – way ANOVA, Duncan test of SPSS software. The Tis coastal seaweed with 9.8% CP, 2% lipid and 23% carbohydrate had higher nutritional value compared to the other gathered seaweed. Also amino acid and fatty acid profiles, vitamins and minerals were measured in all seaweed samples each, with three replications. As result, the water stability of D feed treatment in seawater (98%) and C (97%) had statistical differences with A and B (95% stability) (P0.05) but Cholestrol content of, showed differences between all, significantly (P<0.05) which was the highest (121.68±12.12) in D and the lowest in A (147.92±11.02). Feed treatment D and C performed colour changes pink partial orang and pink in shrimp muscle with no any difference compared to white and none colour in shrimp were fed B and A feed treatments . It seems this colour changing can be playing a major role in market acceptability

The possibility of broodstock production Pinctada margaritifera in response to the dietary treatments

Pearl aquaculture production is one of the most valuable industry in the world. Black lip pearl oyster Pinctada margaritifera is one of the most important commercial species in the world that it is used for breeding and production of pearl. To determine the basic requirements for black lip oyster growth and development of gonad under controlled conditions, Pearl oysters with a total length of 80 mm shells that were in stage 2 maturation of the island Hendorabi collected by diving operations and were transferred to Bandar Lengeh Research Station Persian Gulf mollusks. Pearl oysters with length of 95 mm shells, was passed were all male. 25 percent of them with a total length of 100-110 mm and all with a total length top of 110 mm were female. Then thay were fed for 45 days in appropriate conditions of temperature and photoperiod with March until late spring. Ggreatest physical growth related to Diet with micro-algae Isochrysis sp (T.ISO), Cheatoceros calcitrans, Cheatoceros mullerii, Pavlova lutheri and Tetraselmis suecica, which with the other treatments were significantly different (p<0.05). Most gonadal growth of the group 4 (Isochrysis sp (T.ISO), Pavlova lutheri, Cheatoceros calcitrans, Cheatoceros mullerii) was 70% in the treated females were spawning. Minimum total length of black lip oyster in habitat of 80 mm, which were collected from a depth of 2 meters. There is no relationship between total length Oysters and depth of 4 to 10 meters depth and minimum total length was 115 mm. The most density of Black lip oyster were observed in the depths of 4 to 7 meters in the northwestern part of the island Hendorabi. There were stronger correlation between biometric data, length-weight relative to length- length

Research of possibility of producing of Ice cream through substituting milk protein with condensed protein (FPC) of silver carp

Fish is a valuable nutritional source witch use of it in daily meal has a beneficial role on nutritional needs supply and also causes mental and physical health especially in people who have protein and food deficiencies. Unfortunately, per capita consumption of sea foods in Iran is 5.5Kg which is very lower than world standards (18 kg). So, study on fish ice cream formulation, by use of fish protein concentrate (FPC) instead of milk protein, had done to make variation in sea foods products and also increase per capita consumption of these kinds of foods. FPC has very high protein concentration and a lot of necessary amino acids like lysine and methionine. Also its protein is very digestible with highly biological value and it's PER in compare with casein PER is high. At first fish protein concentrate type A produced from silver carp in three steps by the extraction with isopropyl alcohol solvent and heat. Microbiological and physicochemical specifications of produced FPC by rules of FDA and FAO were accepted. Finally according to panel test results, substitution of 30 percent of milk with FPC in comparison with 50%, 70% FPC substitution prepared (P<0/05). Also microbiological and physicochemical specifications of product were tested and results in compare with national standards of Iran were accepted