[Principles of "ecological living water" to purify sewage and its application in black and smelly water treatment of Yangzhou].

To explore the fundamental way of black and odorous water treatment, based on the study of the purification function of natural water body and the analysis of root cause and direct cause of black and odorous water body, we elaborated the scientific connotation and ecological function of "ecological living water", and fully revealed the scientific principle and technical advantages of "ecological living water" for sewage treatment. "Ecological living water" was the original ecological water control in situ. Through the rapid water reaeration, the micro-ecosystem of living water was created. Meanwhile, with the support of micro-speed circulating water, the continuous and efficient purification was realized. The practice of black and odorous water treatment in Yangzhou showed that, 3-5 days after the treatment of "ecological living water", the black and odorous water was completely eliminated and transformed into "green water". 15-20 days after the treatment, water quality reached the national surface water class 3 water standard. Therefore, "ecological living water" may be a kind of sustainable water control technology system with investment of less resources and equipment, fast pollution control speed, low operation cost, good water control effect and both symptoms and treatment.

Effect of Roughness on the Dispersion of Dry Powders for Inhalation: a Dynamic Visualization Perspective.

Dry powder inhalers have attracted more interest over the years in every aspect related to them. Interestingly, when focusing on the effects of particle morphology of the active or carrier (excipient), it is generally regarded particle size and shape to influence drug availability of aerosolized particles. However, to date, few studies have examined the effect of texture, i.e., roughness, on this relationship. The main objective of the present work is to gain a closer understanding of the influence of carrier morphology on the aerosolization performance of dry powder inhaler formulations. Image analysis and microscopy were used to visualize the aerosolization process. It is considered that the scale of morphological features on the surface of the carrier particles is responsible for the dispersion of the powder formulation, separation of the drug/carrier, and entrainment from a dry powder inhaler. Thus, for this study, the carrier particles of different surface roughness were mixed with micronized salbutamol sulphate. Aerosolization in vitro testing was used to evaluate the performance. The results indicate a connection between the qualitative surface roughness of coarse carriers and aerosolization performance during powder dispersibility. This investigation demonstrated that indeed, powder dispersion, a dynamic process, is influenced by the scale of the carrier morphology.

Preparation of slab-shaped lactose carrier particles for dry powder inhalers by air jet milling.

Dry powder inhalers are often formulated by attaching micronized drug particles onto carrier particles, which are generally lactose. In this study, commercially available lactose was air jet milled to produce unique slab-like coarse carrier particles, which have larger and rougher surfaces compared to other commercially available lactose. Two key processing factors, i.e., classifier speed and jet milling pressure, were systematically investigated. The largest fraction of slab-like particles in the resulting powder was obtained at a classifier speed of 3000 rpm. The slab-like coarse carrier particles are expected to exhibit superior performance than commercial lactose due to their unique surface properties.

Mechanical Properties and Tableting Behavior of Amorphous Solid Dispersions.

Amorphous solid dispersions (ASDs) consisting of acetaminophen (APAP) and copovidone were systematically studied to identify effects of drug loading and moisture content on mechanical properties, thermal properties, and tableting behavior. ASDs containing APAP at different levels were prepared by film casting and characterized by differential scanning calorimetry and nanoindentation. The glass transition temperature (Tg) continuously decreased with increasing amount of APAP, but the hardness of ASDs was increased at a low APAP content and reduced at high APAP content. This in turn significantly influenced tablet quality. Water reduced both the hardness and Tg of ASDs, and the APAP loading level corresponding to the transition to the softening mechanism was lower at a higher relative humidity. Overall, the mechanical properties, rather than the thermal properties, better represent the plasticization/antiplasticization effect of small molecule to ASDs.

Powder dispersion mechanisms within a dry powder inhaler using microscale particle image velocimetry.

The goal of this work was to evaluate the ability of Particle Image Velocimetry (PIV) to visually assess dry powder dispersion within an inhaler. Herein, the study reports particle movement characterization of entrained low-micron particles within an inhaler to further scheme of potential mechanisms. Carrier based DPI formulations were prepared and placed in a transparent model Rotahaler® chamber for the aerosolization experiments. Then using the PIV, a high-speed camera, the dried powder dispersion was directly observed and analyzed for all, neat, binary and ternary systems. Powder dispersion mechanisms proposed include drag force, impact with obstacle and particle-particle collision; these different mechanisms depended on the powder flow properties. A revised ratio of aerodynamic response time (τA) to the mean time between collisions (τC) was found to be 6.8 indicating that particle collisions were of strong influence to particle dispersion. With image analysis techniques, visualization of particle flow pattern and collision regions was possible; suggesting that the various mechanisms proposed did govern the powder dispersion.

Novel coprocessed excipients composed of lactose, HPMC, and PVPP for tableting and its application.

New coprocessed excipients composed of α-lactose monohydrate (a filler), HPMC E3 (a binder), and PVPP (a superdisintegrant) were developed by spray drying in this study to improve the tableting properties of lactose. Factors affecting the properties of the coprocessed excipients were investigated by a 3 × 3 × 2 factorial design. These factors include lactose grade (90 M, 200 M, and 450 M), percentage of HPMC (3.5%, 7.0%, and 10.5%), and percentage of PVPP (0% and 3.5%). The results show that the compactability of the excipients could be significantly improved by increasing either the percentage of HPMC or the primary particle size of lactose. The addition of 3.5% PVPP had little effect on the compactability, but significantly improved the disintegration ability. The developed coprocessed excipients have much lower yield pressures and much higher working efficiency during tableting compared to the main raw material (α-lactose monohydrate). These improvements are mainly attributed to the addition of HPMC and the proximately 30% amorphous lactose formed during process. Both HPMC and amorphous lactose were homogeneously distributed on the surface of the secondary particles, maximizing their effect. Furthermore, the low hygroscopicity and high glass transition temperature of HPMC led to a high yield. The drug loading capacity of the newly coprocessed excipients is also excellent. In summary, the tri-component coprocessed excipients investigated are promising and worthy of further development.

Physico-chemical aspects of lactose for inhalation.

A dry powder inhaler (DPI) is a dosage form that consists of a powder formulation in a device which is designed to deliver an active ingredient to the respiratory tract. It has been extensively investigated over the past years and several aspects relating to device and particulate delivery mechanisms have been the focal points for debate. DPI formulations may or may not contain carrier particles but whenever a carrier is included in a commercial formulation, it is almost invariably lactose monohydrate. Many physicochemical properties of the lactose carrier particles have been reported to affect the efficiency of a DPI. A number of preparation methods have been developed which have been claimed to produce lactose carriers with characteristics which lead to improved deposition. Alongside these developments, a number of characterization methods have been developed which have been reported to be useful in the measurement of key properties of the particulate ingredients. This review describes the various physicochemical characteristics of lactose, methods of manufacturing lactose particulates and their characterization.